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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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/*
*******************************************************************************
*   Copyright (C) 2001-2014, International Business Machines
*   Corporation and others.  All Rights Reserved.
*******************************************************************************
*/

/* FOOD FOR THOUGHT: currently the reordering modes are a mixture of
 * algorithm for direct BiDi, algorithm for inverse Bidi and the bizarre
 * concept of RUNS_ONLY which is a double operation.
 * It could be advantageous to divide this into 3 concepts:
 * a) Operation: direct / inverse / RUNS_ONLY
 * b) Direct algorithm: default / NUMBERS_SPECIAL / GROUP_NUMBERS_WITH_L
 * c) Inverse algorithm: default / INVERSE_LIKE_DIRECT / NUMBERS_SPECIAL
 * This would allow combinations not possible today like RUNS_ONLY with
 * NUMBERS_SPECIAL.
 * Also allow to set INSERT_MARKS for the direct step of RUNS_ONLY and
 * REMOVE_CONTROLS for the inverse step.
 * Not all combinations would be supported, and probably not all do make sense.
 * This would need to document which ones are supported and what are the
 * fallbacks for unsupported combinations.
 */

package jdk_internal.icu.text;

import java.lang.reflect.Array;
import java.util.Arrays;

import jdk_internal.bidi.AttributedCharacterIterator;
import jdk_internal.bidi.Bidi;
import jdk_internal.bidi.NumericShaper;
import jdk_internal.bidi.TextAttribute;
import jdk_internal.icu.impl.UBiDiProps;
import jdk_internal.icu.lang.UCharacter;

/**
 *
 * <h2>Bidi algorithm for ICU</h2>
 *
 * This is an implementation of the Unicode Bidirectional Algorithm. The
 * algorithm is defined in the
 * <a href="http://www.unicode.org/reports/tr9/">Unicode Standard Annex #9:
 * Unicode Bidirectional Algorithm</a>.
 * <p>
 *
 * Note: Libraries that perform a bidirectional algorithm and reorder strings
 * accordingly are sometimes called "Storage Layout Engines". ICU's Bidi and
 * shaping (ArabicShaping) classes can be used at the core of such "Storage
 * Layout Engines".
 *
 * <h3>General remarks about the API:</h3>
 *
 * The "limit" of a sequence of characters is the position just after their last
 * character, i.e., one more than that position.
 * <p>
 *
 * Some of the API methods provide access to "runs". Such a "run" is defined as
 * a sequence of characters that are at the same embedding level after
 * performing the Bidi algorithm.
 *
 * <h3>Basic concept: paragraph</h3> A piece of text can be divided into several
 * paragraphs by characters with the Bidi class <code>Block Separator</code>.
 * For handling of paragraphs, see:
 * <ul>
 * <li>{@link #countParagraphs}
 * <li>{@link #getParaLevel}
 * <li>{@link #getParagraph}
 * <li>{@link #getParagraphByIndex}
 * </ul>
 *
 * <h3>Basic concept: text direction</h3> The direction of a piece of text may
 * be:
 * <ul>
 * <li>{@link #LTR}
 * <li>{@link #RTL}
 * <li>{@link #MIXED}
 * <li>{@link #NEUTRAL}
 * </ul>
 *
 * <h3>Basic concept: levels</h3>
 *
 * Levels in this API represent embedding levels according to the Unicode
 * Bidirectional Algorithm. Their low-order bit (even/odd value) indicates the
 * visual direction.
 * <p>
 *
 * Levels can be abstract values when used for the <code>paraLevel</code> and
 * <code>embeddingLevels</code> arguments of <code>setPara()</code>; there:
 * <ul>
 * <li>the high-order bit of an <code>embeddingLevels[]</code> value indicates
 * whether the using application is specifying the level of a character to
 * <i>override</i> whatever the Bidi implementation would resolve it to.</li>
 * <li><code>paraLevel</code> can be set to the pseudo-level values
 * <code>LEVEL_DEFAULT_LTR</code> and <code>LEVEL_DEFAULT_RTL</code>.</li>
 * </ul>
 *
 * <p>
 * The related constants are not real, valid level values.
 * <code>DEFAULT_XXX</code> can be used to specify a default for the paragraph
 * level for when the <code>setPara()</code> method shall determine it but there
 * is no strongly typed character in the input.
 * <p>
 *
 * Note that the value for <code>LEVEL_DEFAULT_LTR</code> is even and the one
 * for <code>LEVEL_DEFAULT_RTL</code> is odd, just like with normal LTR and RTL
 * level values - these special values are designed that way. Also, the
 * implementation assumes that MAX_EXPLICIT_LEVEL is odd.
 *
 * <p>
 * <b>See Also:</b>
 * <ul>
 * <li>{@link #LEVEL_DEFAULT_LTR}
 * <li>{@link #LEVEL_DEFAULT_RTL}
 * <li>{@link #LEVEL_OVERRIDE}
 * <li>{@link #MAX_EXPLICIT_LEVEL}
 * <li>{@link #setPara}
 * </ul>
 *
 * <h3>Basic concept: Reordering Mode</h3> Reordering mode values indicate which
 * variant of the Bidi algorithm to use.
 *
 * <p>
 * <b>See Also:</b>
 * <ul>
 * <li>{@link #setReorderingMode}
 * <li>{@link #REORDER_DEFAULT}
 * <li>{@link #REORDER_NUMBERS_SPECIAL}
 * <li>{@link #REORDER_GROUP_NUMBERS_WITH_R}
 * <li>{@link #REORDER_RUNS_ONLY}
 * <li>{@link #REORDER_INVERSE_NUMBERS_AS_L}
 * <li>{@link #REORDER_INVERSE_LIKE_DIRECT}
 * <li>{@link #REORDER_INVERSE_FOR_NUMBERS_SPECIAL}
 * </ul>
 *
 * <h3>Basic concept: Reordering Options</h3> Reordering options can be applied
 * during Bidi text transformations.
 *
 * <p>
 * <b>See Also:</b>
 * <ul>
 * <li>{@link #setReorderingOptions}
 * <li>{@link #OPTION_DEFAULT}
 * <li>{@link #OPTION_INSERT_MARKS}
 * <li>{@link #OPTION_REMOVE_CONTROLS}
 * <li>{@link #OPTION_STREAMING}
 * </ul>
 *
 *
 * @author Simon Montagu, Matitiahu Allouche (ported from C code written by
 *         Markus W. Scherer)
 * @stable ICU 3.8
 *
 *
 *         <h4>Sample code for the ICU Bidi API</h4>
 *
 *         <h5>Rendering a paragraph with the ICU Bidi API</h5>
 *
 *         This is (hypothetical) sample code that illustrates how the ICU Bidi
 *         API could be used to render a paragraph of text. Rendering code
 *         depends highly on the graphics system, therefore this sample code
 *         must make a lot of assumptions, which may or may not match any
 *         existing graphics system's properties.
 *
 *         <p>
 *         The basic assumptions are:
 *         </p>
 *         <ul>
 *         <li>Rendering is done from left to right on a horizontal line.</li>
 *         <li>A run of single-style, unidirectional text can be rendered at
 *         once.</li>
 *         <li>Such a run of text is passed to the graphics system with
 *         characters (code units) in logical order.</li>
 *         <li>The line-breaking algorithm is very complicated and
 *         Locale-dependent - and therefore its implementation omitted from this
 *         sample code.</li>
 *         </ul>
 *
 *         <pre>{@code
 *
 *  package com.ibm.icu.dev.test.bidi;
 *
 *  import com.ibm.icu.text.Bidi;
 *  import com.ibm.icu.text.BidiRun;
 *
 *  public class Sample {
 *
 *      static final int styleNormal = 0;
 *      static final int styleSelected = 1;
 *      static final int styleBold = 2;
 *      static final int styleItalics = 4;
 *      static final int styleSuper=8;
 *      static final int styleSub = 16;
 *
 *      static class StyleRun {
 *          int limit;
 *          int style;
 *
 *          public StyleRun(int limit, int style) {
 *              this.limit = limit;
 *              this.style = style;
 *         }
 *         }
 *
 *         static class Bounds {
 *         int start;
 *         int limit;
 *
 *         public Bounds(int start, int limit) {
 *         this.start = start;
 *         this.limit = limit;
 *         }
 *         }
 *
 *         static int getTextWidth(String text, int start, int limit, StyleRun[] styleRuns, int styleRunCount) {
 *         // simplistic way to compute the width
 *         return limit - start;
 *         }
 *
 *         // set limit and StyleRun limit for a line
 *         	// from text[start] and from styleRuns[styleRunStart]
 *         	// using Bidi.getLogicalRun(...)
 *         	// returns line width
 *         static int getLineBreak(String text, Bounds line, Bidi para, StyleRun styleRuns[], Bounds styleRun) {
 *         // dummy return
 *         return 0;
 *         }
 *
 *         // render runs on a line sequentially, always from left to right
 *
 *         // prepare rendering a new line
 *         static void startLine(byte textDirection, int lineWidth) {
 *         System.out.println();
 *         }
 *
 *         // render a run of text and advance to the right by the run width
 *         	// the text[start..limit-1] is always in logical order
 *         static void renderRun(String text, int start, int limit, byte textDirection, int style) {
 *         }
 *
 *         // We could compute a cross-product
 *         	// from the style runs with the directional runs
 *         	// and then reorder it.
 *         	// Instead, here we iterate over each run type
 *         	// and render the intersections -
 *         	// with shortcuts in simple (and common) cases.
 *         	// renderParagraph() is the main function.
 *
 *         // render a directional run with
 *         	// (possibly) multiple style runs intersecting with it
 *         static void renderDirectionalRun(String text, int start, int limit, byte direction, StyleRun styleRuns[],
 *         int styleRunCount) {
 *         int i;
 *
 *         // iterate over style runs
 *         if (direction == Bidi.LTR) {
 *         int styleLimit;
 *         for (i = 0; i < styleRunCount; ++i) {
 *         styleLimit = styleRuns[i].limit;
 *         if (start < styleLimit) {
 *         if (styleLimit > limit) {
 *         styleLimit = limit;
 *         }
 *         renderRun(text, start, styleLimit, direction, styleRuns[i].style);
 *         if (styleLimit == limit) {
 *         break;
 *         }
 *         start = styleLimit;
 *         }
 *         }
 *         } else {
 *         int styleStart;
 *
 *         for (i = styleRunCount - 1; i >= 0; --i) {
 *         if (i > 0) {
 *         styleStart = styleRuns[i - 1].limit;
 *         } else {
 *         styleStart = 0;
 *         }
 *         if (limit >= styleStart) {
 *         if (styleStart < start) {
 *         styleStart = start;
 *         }
 *         renderRun(text, styleStart, limit, direction, styleRuns[i].style);
 *         if (styleStart == start) {
 *         break;
 *         }
 *         limit = styleStart;
 *         }
 *         }
 *         }
 *         }
 *
 *         // the line object represents text[start..limit-1]
 *         static void renderLine(Bidi line, String text, int start, int limit, StyleRun styleRuns[], int styleRunCount) {
 *         byte direction = line.getDirection();
 *         if (direction != Bidi.MIXED) {
 *         // unidirectional
 *         if (styleRunCount <= 1) {
 *         renderRun(text, start, limit, direction, styleRuns[0].style);
 *         } else {
 *         renderDirectionalRun(text, start, limit, direction, styleRuns, styleRunCount);
 *         }
 *         } else {
 *         // mixed-directional
 *         int count, i;
 *         BidiRun run;
 *
 *         try {
 *         count = line.countRuns();
 *         } catch (IllegalStateException e) {
 *         e.printStackTrace();
 *         return;
 *         }
 *         if (styleRunCount <= 1) {
 *         int style = styleRuns[0].style;
 *
 *         // iterate over directional runs
 *         for (i = 0; i < count; ++i) {
 *         run = line.getVisualRun(i);
 *         renderRun(text, run.getStart(), run.getLimit(), run.getDirection(), style);
 *         }
 *         } else {
 *         // iterate over both directional and style runs
 *         for (i = 0; i < count; ++i) {
 *         run = line.getVisualRun(i);
 *         renderDirectionalRun(text, run.getStart(), run.getLimit(), run.getDirection(), styleRuns,
 *         styleRunCount);
 *         }
 *         }
 *         }
 *         }
 *
 *         static void renderParagraph(String text, byte textDirection, StyleRun styleRuns[], int styleRunCount,
 *         int lineWidth) {
 *         int length = text.length();
 *         Bidi para = new Bidi();
 *         try {
 *         para.setPara(text, textDirection != 0 ? Bidi.LEVEL_DEFAULT_RTL : Bidi.LEVEL_DEFAULT_LTR, null);
 *         } catch (Exception e) {
 *         e.printStackTrace();
 *         return;
 *         }
 *         byte paraLevel = (byte) (1 & para.getParaLevel());
 *         StyleRun styleRun = new StyleRun(length, styleNormal);
 *
 *         if (styleRuns == null || styleRunCount <= 0) {
 *         styleRuns = new StyleRun[1];
 *         styleRunCount = 1;
 *         styleRuns[0] = styleRun;
 *         }
 *         // assume styleRuns[styleRunCount-1].limit>=length
 *
 *         int width = getTextWidth(text, 0, length, styleRuns, styleRunCount);
 *         if (width <= lineWidth) {
 *         // everything fits onto one line
 *
 *         // prepare rendering a new line from either left or right
 *         startLine(paraLevel, width);
 *
 *         renderLine(para, text, 0, length, styleRuns, styleRunCount);
 *         } else {
 *         // we need to render several lines
 *         Bidi line = new Bidi(length, 0);
 *         int start = 0, limit;
 *         int styleRunStart = 0, styleRunLimit;
 *
 *         for (;;) {
 *         limit = length;
 *         styleRunLimit = styleRunCount;
 *         width = getLineBreak(text, new Bounds(start, limit), para, styleRuns,
 *         new Bounds(styleRunStart, styleRunLimit));
 *         try {
 *         line = para.setLine(start, limit);
 *         } catch (Exception e) {
 *         e.printStackTrace();
 *         return;
 *         }
 *         // prepare rendering a new line
 *         				// from either left or right
 *         startLine(paraLevel, width);
 *
 *         if (styleRunStart > 0) {
 *         int newRunCount = styleRuns.length - styleRunStart;
 *         StyleRun[] newRuns = new StyleRun[newRunCount];
 *         System.arraycopy(styleRuns, styleRunStart, newRuns, 0, newRunCount);
 *         renderLine(line, text, start, limit, newRuns, styleRunLimit - styleRunStart);
 *         } else {
 *         renderLine(line, text, start, limit, styleRuns, styleRunLimit - styleRunStart);
 *         }
 *         if (limit == length) {
 *         break;
 *         }
 *         start = limit;
 *         styleRunStart = styleRunLimit - 1;
 *         if (start >= styleRuns[styleRunStart].limit) {
 *         ++styleRunStart;
 *         }
 *         }
 *         }
 *         }
 *
 *         public static void main(String[] args) {
 *         renderParagraph("Some Latin text...", Bidi.LTR, null, 0, 80);
 *         renderParagraph("Some Hebrew text...", Bidi.RTL, null, 0, 60);
 *         }
 *         }
 *
 * }</pre>
 */

/*
 * General implementation notes:
 *
 * Throughout the implementation, there are comments like (W2) that refer to
 * rules of the BiDi algorithm, in this example to the second rule of the
 * resolution of weak types.
 *
 * For handling surrogate pairs, where two UChar's form one "abstract" (or
 * UTF-32) character according to UTF-16, the second UChar gets the directional
 * property of the entire character assigned, while the first one gets a BN, a
 * boundary neutral, type, which is ignored by most of the algorithm according
 * to rule (X9) and the implementation suggestions of the BiDi algorithm.
 *
 * Later, adjustWSLevels() will set the level for each BN to that of the
 * following character (UChar), which results in surrogate pairs getting the
 * same level on each of their surrogates.
 *
 * In a UTF-8 implementation, the same thing could be done: the last byte of a
 * multi-byte sequence would get the "real" property, while all previous bytes
 * of that sequence would get BN.
 *
 * It is not possible to assign all those parts of a character the same real
 * property because this would fail in the resolution of weak types with rules
 * that look at immediately surrounding types.
 *
 * As a related topic, this implementation does not remove Boundary Neutral
 * types from the input, but ignores them wherever this is relevant. For
 * example, the loop for the resolution of the weak types reads types until it
 * finds a non-BN. Also, explicit embedding codes are neither changed into BN
 * nor removed. They are only treated the same way real BNs are. As stated
 * before, adjustWSLevels() takes care of them at the end. For the purpose of
 * conformance, the levels of all these codes do not matter.
 *
 * Note that this implementation modifies the dirProps after the initial setup,
 * when applying X5c (replace FSI by LRI or RLI), X6, N0 (replace paired
 * brackets by L or R).
 *
 * In this implementation, the resolution of weak types (W1 to W6), neutrals (N1
 * and N2), and the assignment of the resolved level (In) are all done in one
 * single loop, in resolveImplicitLevels(). Changes of dirProp values are done
 * on the fly, without writing them back to the dirProps array.
 *
 *
 * This implementation contains code that allows to bypass steps of the
 * algorithm that are not needed on the specific paragraph in order to speed up
 * the most common cases considerably, like text that is entirely LTR, or RTL
 * text without numbers.
 *
 * Most of this is done by setting a bit for each directional property in a
 * flags variable and later checking for whether there are any LTR characters or
 * any RTL characters, or both, whether there are any explicit embedding codes,
 * etc.
 *
 * If the (Xn) steps are performed, then the flags are re-evaluated, because
 * they will then not contain the embedding codes any more and will be adjusted
 * for override codes, so that subsequently more bypassing may be possible than
 * what the initial flags suggested.
 *
 * If the text is not mixed-directional, then the algorithm steps for the weak
 * type resolution are not performed, and all levels are set to the paragraph
 * level.
 *
 * If there are no explicit embedding codes, then the (Xn) steps are not
 * performed.
 *
 * If embedding levels are supplied as a parameter, then all explicit embedding
 * codes are ignored, and the (Xn) steps are not performed.
 *
 * White Space types could get the level of the run they belong to, and are
 * checked with a test of (flags&MASK_EMBEDDING) to consider if the paragraph
 * direction should be considered in the flags variable.
 *
 * If there are no White Space types in the paragraph, then (L1) is not
 * necessary in adjustWSLevels().
 */

// Original filename in ICU4J: Bidi.java
public class BidiBase {

	/**
	 * Bidi Paired Bracket Type constants.
	 *
	 * @see UProperty#BIDI_PAIRED_BRACKET_TYPE
	 * @stable ICU 52
	 */
	public static interface BidiPairedBracketType {
		/**
		 * Not a paired bracket.
		 *
		 * @stable ICU 52
		 */
		public static final int NONE = 0;
		/**
		 * Open paired bracket.
		 *
		 * @stable ICU 52
		 */
		public static final int OPEN = 1;
		/**
		 * Close paired bracket.
		 *
		 * @stable ICU 52
		 */
		public static final int CLOSE = 2;
		/**
		 * @stable ICU 52
		 */
		public static final int COUNT = 3;
	}

	static class BracketData {
		Opening[] openings = new Opening[SIMPLE_PARAS_COUNT];
		int isoRunLast; /* index of last used entry */
		/*
		 * array of nested isolated sequence entries; can never excess
		 * UBIDI_MAX_EXPLICIT_LEVEL + 1 for index 0, + 1 for before the first isolated
		 * sequence
		 */
		IsoRun[] isoRuns = new IsoRun[MAX_EXPLICIT_LEVEL + 2];
		boolean isNumbersSpecial; /* reordering mode for NUMBERS_SPECIAL */
	}

	private static class ImpTabPair {
		byte[][][] imptab;
		short[][] impact;

		ImpTabPair(byte[][] table1, byte[][] table2, short[] act1, short[] act2) {
			imptab = new byte[][][] { table1, table2 };
			impact = new short[][] { act1, act2 };
		}
	}

	static class InsertPoints {
		int size;
		int confirmed;
		Point[] points = new Point[0];
	}

	static class Isolate {
		int startON;
		int start1;
		short stateImp;
		short state;
	}

	static class IsoRun {
		int contextPos; /* position of char determining context */
		short start; /* index of first opening entry for this run */
		short limit; /* index after last opening entry for this run */
		byte level; /* level of this run */
		byte lastStrong; /* bidi class of last strong char found in this run */
		byte lastBase; /* bidi class of last base char found in this run */
		byte contextDir; /* L or R to use as context for following openings */
	}

	private static class LevState {
		byte[][] impTab; /* level table pointer */
		short[] impAct; /* action map array */
		int startON; /* start of ON sequence */
		int startL2EN; /* start of level 2 sequence */
		int lastStrongRTL; /* index of last found R or AL */
		int runStart; /* start position of the run */
		short state; /* current state */
		byte runLevel; /* run level before implicit solving */
	}

	static class Opening {
		int position; /* position of opening bracket */
		int match; /* matching char or -position of closing bracket */
		int contextPos; /* position of last strong char found before opening */
		short flags; /* bits for L or R/AL found within the pair */
		byte contextDir; /* L or R according to last strong char before opening */
	}

	static class Point {
		int pos; /* position in text */
		int flag; /* flag for LRM/RLM, before/after */
	}

	/**
	 * Paragraph level setting
	 * <p>
	 *
	 * Constant indicating that the base direction depends on the first strong
	 * directional character in the text according to the Unicode Bidirectional
	 * Algorithm. If no strong directional character is present, then set the
	 * paragraph level to 0 (left-to-right).
	 * <p>
	 *
	 * If this value is used in conjunction with reordering modes
	 * <code>REORDER_INVERSE_LIKE_DIRECT</code> or
	 * <code>REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder is
	 * assumed to be visual LTR, and the text after reordering is required to be the
	 * corresponding logical string with appropriate contextual direction. The
	 * direction of the result string will be RTL if either the rightmost or
	 * leftmost strong character of the source text is RTL or Arabic Letter, the
	 * direction will be LTR otherwise.
	 * <p>
	 *
	 * If reordering option <code>OPTION_INSERT_MARKS</code> is set, an RLM may be
	 * added at the beginning of the result string to ensure round trip (that the
	 * result string, when reordered back to visual, will produce the original
	 * source text).
	 *
	 * @see #REORDER_INVERSE_LIKE_DIRECT
	 * @see #REORDER_INVERSE_FOR_NUMBERS_SPECIAL
	 * @stable ICU 3.8
	 */
	public static final byte LEVEL_DEFAULT_LTR = (byte) 0x7e;

	/**
	 * Paragraph level setting
	 * <p>
	 *
	 * Constant indicating that the base direction depends on the first strong
	 * directional character in the text according to the Unicode Bidirectional
	 * Algorithm. If no strong directional character is present, then set the
	 * paragraph level to 1 (right-to-left).
	 * <p>
	 *
	 * If this value is used in conjunction with reordering modes
	 * <code>REORDER_INVERSE_LIKE_DIRECT</code> or
	 * <code>REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder is
	 * assumed to be visual LTR, and the text after reordering is required to be the
	 * corresponding logical string with appropriate contextual direction. The
	 * direction of the result string will be RTL if either the rightmost or
	 * leftmost strong character of the source text is RTL or Arabic Letter, or if
	 * the text contains no strong character; the direction will be LTR otherwise.
	 * <p>
	 *
	 * If reordering option <code>OPTION_INSERT_MARKS</code> is set, an RLM may be
	 * added at the beginning of the result string to ensure round trip (that the
	 * result string, when reordered back to visual, will produce the original
	 * source text).
	 *
	 * @see #REORDER_INVERSE_LIKE_DIRECT
	 * @see #REORDER_INVERSE_FOR_NUMBERS_SPECIAL
	 * @stable ICU 3.8
	 */
	public static final byte LEVEL_DEFAULT_RTL = (byte) 0x7f;

	/**
	 * Maximum explicit embedding level. (The maximum resolved level can be up to
	 * <code>MAX_EXPLICIT_LEVEL+1</code>).
	 *
	 * @stable ICU 3.8
	 */
	public static final byte MAX_EXPLICIT_LEVEL = 125;

	/**
	 * Bit flag for level input. Overrides directional properties.
	 *
	 * @stable ICU 3.8
	 */
	public static final byte LEVEL_OVERRIDE = (byte) 0x80;

	/**
	 * Special value which can be returned by the mapping methods when a logical
	 * index has no corresponding visual index or vice-versa. This may happen for
	 * the logical-to-visual mapping of a Bidi control when option
	 * <code>OPTION_REMOVE_CONTROLS</code> is specified. This can also happen for
	 * the visual-to-logical mapping of a Bidi mark (LRM or RLM) inserted by option
	 * <code>OPTION_INSERT_MARKS</code>.
	 *
	 * @see #getVisualIndex
	 * @see #getVisualMap
	 * @see #getLogicalIndex
	 * @see #getLogicalMap
	 * @see #OPTION_INSERT_MARKS
	 * @see #OPTION_REMOVE_CONTROLS
	 * @stable ICU 3.8
	 */
	public static final int MAP_NOWHERE = -1;

	/**
	 * Left-to-right text.
	 * <ul>
	 * <li>As return value for <code>getDirection()</code>, it means that the source
	 * string contains no right-to-left characters, or that the source string is
	 * empty and the paragraph level is even.
	 * <li>As return value for <code>getBaseDirection()</code>, it means that the
	 * first strong character of the source string has a left-to-right direction.
	 * </ul>
	 *
	 * @stable ICU 3.8
	 */
	public static final byte LTR = 0;

	/**
	 * Right-to-left text.
	 * <ul>
	 * <li>As return value for <code>getDirection()</code>, it means that the source
	 * string contains no left-to-right characters, or that the source string is
	 * empty and the paragraph level is odd.
	 * <li>As return value for <code>getBaseDirection()</code>, it means that the
	 * first strong character of the source string has a right-to-left direction.
	 * </ul>
	 *
	 * @stable ICU 3.8
	 */
	public static final byte RTL = 1;

	/**
	 * Mixed-directional text.
	 * <p>
	 * As return value for <code>getDirection()</code>, it means that the source
	 * string contains both left-to-right and right-to-left characters.
	 *
	 * @stable ICU 3.8
	 */
	public static final byte MIXED = 2;

	/**
	 * option bit for writeReordered(): keep combining characters after their base
	 * characters in RTL runs
	 *
	 * @see #writeReordered
	 * @stable ICU 3.8
	 */
	public static final short KEEP_BASE_COMBINING = 1;

	/**
	 * option bit for writeReordered(): replace characters with the "mirrored"
	 * property in RTL runs by their mirror-image mappings
	 *
	 * @see #writeReordered
	 * @stable ICU 3.8
	 */
	public static final short DO_MIRRORING = 2;

	/**
	 * option bit for writeReordered(): surround the run with LRMs if necessary;
	 * this is part of the approximate "inverse Bidi" algorithm
	 *
	 * <p>
	 * This option does not imply corresponding adjustment of the index mappings.
	 * </p>
	 *
	 * @see #setInverse
	 * @see #writeReordered
	 * @stable ICU 3.8
	 */
	public static final short INSERT_LRM_FOR_NUMERIC = 4;

	/**
	 * option bit for writeReordered(): remove Bidi control characters (this does
	 * not affect INSERT_LRM_FOR_NUMERIC)
	 *
	 * <p>
	 * This option does not imply corresponding adjustment of the index mappings.
	 * </p>
	 *
	 * @see #writeReordered
	 * @see #INSERT_LRM_FOR_NUMERIC
	 * @stable ICU 3.8
	 */
	public static final short REMOVE_BIDI_CONTROLS = 8;

	/**
	 * option bit for writeReordered(): write the output in reverse order
	 *
	 * <p>
	 * This has the same effect as calling <code>writeReordered()</code> first
	 * without this option, and then calling <code>writeReverse()</code> without
	 * mirroring. Doing this in the same step is faster and avoids a temporary
	 * buffer. An example for using this option is output to a character terminal
	 * that is designed for RTL scripts and stores text in reverse order.
	 * </p>
	 *
	 * @see #writeReordered
	 * @stable ICU 3.8
	 */
	public static final short OUTPUT_REVERSE = 16;

	/**
	 * Reordering mode: Regular Logical to Visual Bidi algorithm according to
	 * Unicode.
	 *
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	private static final short REORDER_DEFAULT = 0;

	/**
	 * Reordering mode: Logical to Visual algorithm which handles numbers in a way
	 * which mimicks the behavior of Windows XP.
	 *
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	private static final short REORDER_NUMBERS_SPECIAL = 1;

	/**
	 * Reordering mode: Logical to Visual algorithm grouping numbers with adjacent R
	 * characters (reversible algorithm).
	 *
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	private static final short REORDER_GROUP_NUMBERS_WITH_R = 2;

	/**
	 * Reordering mode: Reorder runs only to transform a Logical LTR string to the
	 * logical RTL string with the same display, or vice-versa.<br>
	 * If this mode is set together with option <code>OPTION_INSERT_MARKS</code>,
	 * some Bidi controls in the source text may be removed and other controls may
	 * be added to produce the minimum combination which has the required display.
	 *
	 * @see #OPTION_INSERT_MARKS
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	static final short REORDER_RUNS_ONLY = 3;

	/**
	 * Reordering mode: Visual to Logical algorithm which handles numbers like L
	 * (same algorithm as selected by <code>setInverse(true)</code>.
	 *
	 * @see #setInverse
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	static final short REORDER_INVERSE_NUMBERS_AS_L = 4;

	/**
	 * Reordering mode: Visual to Logical algorithm equivalent to the regular
	 * Logical to Visual algorithm.
	 *
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	static final short REORDER_INVERSE_LIKE_DIRECT = 5;

	/**
	 * Reordering mode: Inverse Bidi (Visual to Logical) algorithm for the
	 * <code>REORDER_NUMBERS_SPECIAL</code> Bidi algorithm.
	 *
	 * @see #setReorderingMode
	 * @stable ICU 3.8
	 */
	static final short REORDER_INVERSE_FOR_NUMBERS_SPECIAL = 6;

	/*
	 * Reordering mode values must be ordered so that all the regular logical to
	 * visual modes come first, and all inverse Bidi modes come last.
	 */
	private static final short REORDER_LAST_LOGICAL_TO_VISUAL = REORDER_NUMBERS_SPECIAL;

	/**
	 * Option bit for <code>setReorderingOptions</code>: insert Bidi marks (LRM or
	 * RLM) when needed to ensure correct result of a reordering to a Logical order
	 *
	 * <p>
	 * This option must be set or reset before calling <code>setPara</code>.
	 * </p>
	 *
	 * <p>
	 * This option is significant only with reordering modes which generate a result
	 * with Logical order, specifically.
	 * </p>
	 * <ul>
	 * <li><code>REORDER_RUNS_ONLY</code></li>
	 * <li><code>REORDER_INVERSE_NUMBERS_AS_L</code></li>
	 * <li><code>REORDER_INVERSE_LIKE_DIRECT</code></li>
	 * <li><code>REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code></li>
	 * </ul>
	 *
	 * <p>
	 * If this option is set in conjunction with reordering mode
	 * <code>REORDER_INVERSE_NUMBERS_AS_L</code> or with calling
	 * <code>setInverse(true)</code>, it implies option
	 * <code>INSERT_LRM_FOR_NUMERIC</code> in calls to method
	 * <code>writeReordered()</code>.
	 * </p>
	 *
	 * <p>
	 * For other reordering modes, a minimum number of LRM or RLM characters will be
	 * added to the source text after reordering it so as to ensure round trip, i.e.
	 * when applying the inverse reordering mode on the resulting logical text with
	 * removal of Bidi marks (option <code>OPTION_REMOVE_CONTROLS</code> set before
	 * calling <code>setPara()</code> or option <code>REMOVE_BIDI_CONTROLS</code> in
	 * <code>writeReordered</code>), the result will be identical to the source text
	 * in the first transformation.
	 *
	 * <p>
	 * This option will be ignored if specified together with option
	 * <code>OPTION_REMOVE_CONTROLS</code>. It inhibits option
	 * <code>REMOVE_BIDI_CONTROLS</code> in calls to method
	 * <code>writeReordered()</code> and it implies option
	 * <code>INSERT_LRM_FOR_NUMERIC</code> in calls to method
	 * <code>writeReordered()</code> if the reordering mode is
	 * <code>REORDER_INVERSE_NUMBERS_AS_L</code>.
	 * </p>
	 *
	 * @see #setReorderingMode
	 * @see #setReorderingOptions
	 * @see #INSERT_LRM_FOR_NUMERIC
	 * @see #REMOVE_BIDI_CONTROLS
	 * @see #OPTION_REMOVE_CONTROLS
	 * @see #REORDER_RUNS_ONLY
	 * @see #REORDER_INVERSE_NUMBERS_AS_L
	 * @see #REORDER_INVERSE_LIKE_DIRECT
	 * @see #REORDER_INVERSE_FOR_NUMBERS_SPECIAL
	 * @stable ICU 3.8
	 */
	static final int OPTION_INSERT_MARKS = 1;
	/**
	 * Option bit for <code>setReorderingOptions</code>: remove Bidi control
	 * characters
	 *
	 * <p>
	 * This option must be set or reset before calling <code>setPara</code>.
	 * </p>
	 *
	 * <p>
	 * This option nullifies option <code>OPTION_INSERT_MARKS</code>. It inhibits
	 * option <code>INSERT_LRM_FOR_NUMERIC</code> in calls to method
	 * <code>writeReordered()</code> and it implies option
	 * <code>REMOVE_BIDI_CONTROLS</code> in calls to that method.
	 * </p>
	 *
	 * @see #setReorderingMode
	 * @see #setReorderingOptions
	 * @see #OPTION_INSERT_MARKS
	 * @see #INSERT_LRM_FOR_NUMERIC
	 * @see #REMOVE_BIDI_CONTROLS
	 * @stable ICU 3.8
	 */
	static final int OPTION_REMOVE_CONTROLS = 2;
	/**
	 * Option bit for <code>setReorderingOptions</code>: process the output as part
	 * of a stream to be continued
	 *
	 * <p>
	 * This option must be set or reset before calling <code>setPara</code>.
	 * </p>
	 *
	 * <p>
	 * This option specifies that the caller is interested in processing large text
	 * object in parts. The results of the successive calls are expected to be
	 * concatenated by the caller. Only the call for the last part will have this
	 * option bit off.
	 * </p>
	 *
	 * <p>
	 * When this option bit is on, <code>setPara()</code> may process less than the
	 * full source text in order to truncate the text at a meaningful boundary. The
	 * caller should call <code>getProcessedLength()</code> immediately after
	 * calling <code>setPara()</code> in order to determine how much of the source
	 * text has been processed. Source text beyond that length should be resubmitted
	 * in following calls to <code>setPara</code>. The processed length may be less
	 * than the length of the source text if a character preceding the last
	 * character of the source text constitutes a reasonable boundary (like a block
	 * separator) for text to be continued.<br>
	 * If the last character of the source text constitutes a reasonable boundary,
	 * the whole text will be processed at once.<br>
	 * If nowhere in the source text there exists such a reasonable boundary, the
	 * processed length will be zero.<br>
	 * The caller should check for such an occurrence and do one of the following:
	 * <ul>
	 * <li>submit a larger amount of text with a better chance to include a
	 * reasonable boundary.</li>
	 * <li>resubmit the same text after turning off option
	 * <code>OPTION_STREAMING</code>.</li>
	 * </ul>
	 * In all cases, this option should be turned off before processing the last
	 * part of the text.
	 * </p>
	 *
	 * <p>
	 * When the <code>OPTION_STREAMING</code> option is used, it is recommended to
	 * call <code>orderParagraphsLTR(true)</code> before calling
	 * <code>setPara()</code> so that later paragraphs may be concatenated to
	 * previous paragraphs on the right.
	 * </p>
	 *
	 * @see #setReorderingMode
	 * @see #setReorderingOptions
	 * @see #getProcessedLength
	 * @stable ICU 3.8
	 */
	private static final int OPTION_STREAMING = 4;
	/*
	 * Comparing the description of the Bidi algorithm with this implementation is
	 * easier with the same names for the Bidi types in the code as there. See
	 * UCharacterDirection
	 */
	/* private */ static final byte L = 0;
	private static final byte R = 1;
	private static final byte EN = 2;
	private static final byte ES = 3;
	private static final byte ET = 4;
	private static final byte AN = 5;
	private static final byte CS = 6;
	static final byte B = 7;
	private static final byte S = 8;
	private static final byte WS = 9;
	private static final byte ON = 10;
	private static final byte LRE = 11;
	private static final byte LRO = 12;
	private static final byte AL = 13;
	private static final byte RLE = 14;
	private static final byte RLO = 15;
	private static final byte PDF = 16;
	private static final byte NSM = 17;
	private static final byte BN = 18;
	private static final byte FSI = 19;
	private static final byte LRI = 20;
	private static final byte RLI = 21;

	private static final byte PDI = 22;

	private static final byte ENL = PDI + 1; /* EN after W7 */

	private static final byte ENR = ENL + 1; /* EN not subject to W7 */

	// Number of directional types
	private static final int CHAR_DIRECTION_COUNT = 23;

	/**
	 * Enumerated property Bidi_Paired_Bracket_Type (new in Unicode 6.3). Used in
	 * <a href="http://www.unicode.org/reports/tr9/">Unicode Standard Annex #9:
	 * Unicode Bidirectional Algorithm</a>. Returns UCharacter.BidiPairedBracketType
	 * values.
	 *
	 * @stable ICU 52
	 */
	public static final int BIDI_PAIRED_BRACKET_TYPE = 0x1015;
	/* number of paras entries allocated initially */
	static final int SIMPLE_PARAS_COUNT = 10;

	private static final char CR = '\r';
	private static final char LF = '\n';
	static final int LRM_BEFORE = 1;
	static final int LRM_AFTER = 2;

	static final int RLM_BEFORE = 4;
	static final int RLM_AFTER = 8;

	/* flags for Opening.flags */
	static final byte FOUND_L = (byte) DirPropFlag(L);

	static final byte FOUND_R = (byte) DirPropFlag(R);

	/*
	 * The following bit is used for the directional isolate status. Stack entries
	 * corresponding to isolate sequences are greater than ISOLATE.
	 */
	static final int ISOLATE = 0x0100;

	static final int DirPropFlagMultiRuns = DirPropFlag((byte) 31);

	/* to avoid some conditional statements, use tiny constant arrays */
	static final int DirPropFlagLR[] = { DirPropFlag(L), DirPropFlag(R) };

	static final int DirPropFlagE[] = { DirPropFlag(LRE), DirPropFlag(RLE) };

	static final int DirPropFlagO[] = { DirPropFlag(LRO), DirPropFlag(RLO) };

	/* are there any characters that are LTR or RTL? */
	static final int MASK_LTR = DirPropFlag(L) | DirPropFlag(EN) | DirPropFlag(ENL) | DirPropFlag(ENR) | DirPropFlag(AN)
			| DirPropFlag(LRE) | DirPropFlag(LRO) | DirPropFlag(LRI);
	static final int MASK_RTL = DirPropFlag(R) | DirPropFlag(AL) | DirPropFlag(RLE) | DirPropFlag(RLO)
			| DirPropFlag(RLI);

	static final int MASK_R_AL = DirPropFlag(R) | DirPropFlag(AL);
	/* explicit embedding codes */
	private static final int MASK_EXPLICIT = DirPropFlag(LRE) | DirPropFlag(LRO) | DirPropFlag(RLE) | DirPropFlag(RLO)
			| DirPropFlag(PDF);
	private static final int MASK_BN_EXPLICIT = DirPropFlag(BN) | MASK_EXPLICIT;
	/* explicit isolate codes */
	private static final int MASK_ISO = DirPropFlag(LRI) | DirPropFlag(RLI) | DirPropFlag(FSI) | DirPropFlag(PDI);

	/* paragraph and segment separators */
	private static final int MASK_B_S = DirPropFlag(B) | DirPropFlag(S);

	/* all types that are counted as White Space or Neutral in some steps */
	static final int MASK_WS = MASK_B_S | DirPropFlag(WS) | MASK_BN_EXPLICIT | MASK_ISO;

	/* types that are neutrals or could becomes neutrals in (Wn) */
	private static final int MASK_POSSIBLE_N = DirPropFlag(ON) | DirPropFlag(CS) | DirPropFlag(ES) | DirPropFlag(ET)
			| MASK_WS;

	/*
	 * These types may be changed to "e", the embedding type (L or R) of the run, in
	 * the Bidi algorithm (N2)
	 */
	private static final int MASK_EMBEDDING = DirPropFlag(NSM) | MASK_POSSIBLE_N;

	/*
	 * Get the directional properties for the text, calculate the flags bit-set, and
	 * determine the paragraph level if necessary (in paras_level[i]). FSI
	 * initiators are also resolved and their dirProp replaced with LRI or RLI. When
	 * encountering an FSI, it is initially replaced with an LRI, which is the
	 * default. Only if a strong R or AL is found within its scope will the LRI be
	 * replaced by an RLI.
	 */
	static final int NOT_SEEKING_STRONG = 0; /* 0: not contextual paraLevel, not after FSI */

	static final int SEEKING_STRONG_FOR_PARA = 1; /* 1: looking for first strong char in para */

	/* the following is set in setPara, used in processPropertySeq */

	static final int SEEKING_STRONG_FOR_FSI = 2; /* 2: looking for first strong after FSI */

	static final int LOOKING_FOR_PDI = 3; /* 3: found strong after FSI, looking for PDI */

	/* Definitions and type for properties state tables */
	/*********************************************************************/
	private static final int IMPTABPROPS_COLUMNS = 16;

	private static final int IMPTABPROPS_RES = IMPTABPROPS_COLUMNS - 1;

	private static final short groupProp[] = /* dirProp regrouped */
			{
					/*
					 * L R EN ES ET AN CS B S WS ON LRE LRO AL RLE RLO PDF NSM BN FSI LRI RLI PDI
					 * ENL ENR
					 */
					0, 1, 2, 7, 8, 3, 9, 6, 5, 4, 4, 10, 10, 12, 10, 10, 10, 11, 10, 4, 4, 4, 4, 13, 14 };

	private static final short _L = 0;
	private static final short _R = 1;
	private static final short _EN = 2;

	private static final short _AN = 3;
	private static final short _ON = 4;
	private static final short _S = 5;

	private static final short _B = 6; /* reduced dirProp */

	/*********************************************************************/
	/*                                                                   */
	/* PROPERTIES STATE TABLE */
	/*                                                                   */
	/* In table impTabProps, */
	/* - the ON column regroups ON and WS, FSI, RLI, LRI and PDI */
	/* - the BN column regroups BN, LRE, RLE, LRO, RLO, PDF */
	/* - the Res column is the reduced property assigned to a run */
	/*                                                                   */
	/* Action 1: process current run1, init new run1 */
	/* 2: init new run2 */
	/* 3: process run1, process run2, init new run1 */
	/* 4: process run1, set run1=run2, init new run2 */
	/*                                                                   */
	/* Notes: */
	/* 1) This table is used in resolveImplicitLevels(). */
	/* 2) This table triggers actions when there is a change in the Bidi */
	/* property of incoming characters (action 1). */
	/* 3) Most such property sequences are processed immediately (in */
	/* fact, passed to processPropertySeq(). */
	/* 4) However, numbers are assembled as one sequence. This means */
	/* that undefined situations (like CS following digits, until */
	/* it is known if the next char will be a digit) are held until */
	/* following chars define them. */
	/* Example: digits followed by CS, then comes another CS or ON; */
	/* the digits will be processed, then the CS assigned */
	/* as the start of an ON sequence (action 3). */
	/* 5) There are cases where more than one sequence must be */
	/* processed, for instance digits followed by CS followed by L: */
	/* the digits must be processed as one sequence, and the CS */
	/* must be processed as an ON sequence, all this before starting */
	/* assembling chars for the opening L sequence. */
	/*                                                                   */
	/*                                                                   */
	private static final short impTabProps[][] = {
			/* L, R, EN, AN, ON, S, B, ES, ET, CS, BN, NSM, AL, ENL, ENR, Res */
			/* 0 Init */ { 1, 2, 4, 5, 7, 15, 17, 7, 9, 7, 0, 7, 3, 18, 21, _ON },
			/* 1 L */ { 1, 32 + 2, 32 + 4, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 32 + 9, 32 + 7, 1, 1, 32 + 3,
					32 + 18, 32 + 21, _L },
			/* 2 R */ { 32 + 1, 2, 32 + 4, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 32 + 9, 32 + 7, 2, 2, 32 + 3,
					32 + 18, 32 + 21, _R },
			/* 3 AL */ { 32 + 1, 32 + 2, 32 + 6, 32 + 6, 32 + 8, 32 + 16, 32 + 17, 32 + 8, 32 + 8, 32 + 8, 3, 3, 3,
					32 + 18, 32 + 21, _R },
			/* 4 EN */ { 32 + 1, 32 + 2, 4, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 64 + 10, 11, 64 + 10, 4, 4, 32 + 3, 18,
					21, _EN },
			/* 5 AN */ { 32 + 1, 32 + 2, 32 + 4, 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 32 + 9, 64 + 12, 5, 5, 32 + 3,
					32 + 18, 32 + 21, _AN },
			/* 6 AL:EN/AN */ { 32 + 1, 32 + 2, 6, 6, 32 + 8, 32 + 16, 32 + 17, 32 + 8, 32 + 8, 64 + 13, 6, 6, 32 + 3,
					18, 21, _AN },
			/* 7 ON */ { 32 + 1, 32 + 2, 32 + 4, 32 + 5, 7, 32 + 15, 32 + 17, 7, 64 + 14, 7, 7, 7, 32 + 3, 32 + 18,
					32 + 21, _ON },
			/* 8 AL:ON */ { 32 + 1, 32 + 2, 32 + 6, 32 + 6, 8, 32 + 16, 32 + 17, 8, 8, 8, 8, 8, 32 + 3, 32 + 18,
					32 + 21, _ON },
			/* 9 ET */ { 32 + 1, 32 + 2, 4, 32 + 5, 7, 32 + 15, 32 + 17, 7, 9, 7, 9, 9, 32 + 3, 18, 21, _ON },
			/* 10 EN+ES/CS */ { 96 + 1, 96 + 2, 4, 96 + 5, 128 + 7, 96 + 15, 96 + 17, 128 + 7, 128 + 14, 128 + 7, 10,
					128 + 7, 96 + 3, 18, 21, _EN },
			/* 11 EN+ET */ { 32 + 1, 32 + 2, 4, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 11, 32 + 7, 11, 11, 32 + 3,
					18, 21, _EN },
			/* 12 AN+CS */ { 96 + 1, 96 + 2, 96 + 4, 5, 128 + 7, 96 + 15, 96 + 17, 128 + 7, 128 + 14, 128 + 7, 12,
					128 + 7, 96 + 3, 96 + 18, 96 + 21, _AN },
			/* 13 AL:EN/AN+CS */ { 96 + 1, 96 + 2, 6, 6, 128 + 8, 96 + 16, 96 + 17, 128 + 8, 128 + 8, 128 + 8, 13,
					128 + 8, 96 + 3, 18, 21, _AN },
			/* 14 ON+ET */ { 32 + 1, 32 + 2, 128 + 4, 32 + 5, 7, 32 + 15, 32 + 17, 7, 14, 7, 14, 14, 32 + 3, 128 + 18,
					128 + 21, _ON },
			/* 15 S */ { 32 + 1, 32 + 2, 32 + 4, 32 + 5, 32 + 7, 15, 32 + 17, 32 + 7, 32 + 9, 32 + 7, 15, 32 + 7,
					32 + 3, 32 + 18, 32 + 21, _S },
			/* 16 AL:S */ { 32 + 1, 32 + 2, 32 + 6, 32 + 6, 32 + 8, 16, 32 + 17, 32 + 8, 32 + 8, 32 + 8, 16, 32 + 8,
					32 + 3, 32 + 18, 32 + 21, _S },
			/* 17 B */ { 32 + 1, 32 + 2, 32 + 4, 32 + 5, 32 + 7, 32 + 15, 17, 32 + 7, 32 + 9, 32 + 7, 17, 32 + 7,
					32 + 3, 32 + 18, 32 + 21, _B },
			/* 18 ENL */ { 32 + 1, 32 + 2, 18, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 64 + 19, 20, 64 + 19, 18, 18, 32 + 3,
					18, 21, _L },
			/* 19 ENL+ES/CS */ { 96 + 1, 96 + 2, 18, 96 + 5, 128 + 7, 96 + 15, 96 + 17, 128 + 7, 128 + 14, 128 + 7, 19,
					128 + 7, 96 + 3, 18, 21, _L },
			/* 20 ENL+ET */ { 32 + 1, 32 + 2, 18, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 20, 32 + 7, 20, 20, 32 + 3,
					18, 21, _L },
			/* 21 ENR */ { 32 + 1, 32 + 2, 21, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 64 + 22, 23, 64 + 22, 21, 21, 32 + 3,
					18, 21, _AN },
			/* 22 ENR+ES/CS */ { 96 + 1, 96 + 2, 21, 96 + 5, 128 + 7, 96 + 15, 96 + 17, 128 + 7, 128 + 14, 128 + 7, 22,
					128 + 7, 96 + 3, 18, 21, _AN },
			/* 23 ENR+ET */ { 32 + 1, 32 + 2, 21, 32 + 5, 32 + 7, 32 + 15, 32 + 17, 32 + 7, 23, 32 + 7, 23, 23, 32 + 3,
					18, 21, _AN } };

	/*********************************************************************/
	/* The levels state machine tables */
	/*********************************************************************/
	/*                                                                   */
	/* All table cells are 8 bits: */
	/* bits 0..3: next state */
	/* bits 4..7: action to perform (if > 0) */
	/*                                                                   */
	/* Cells may be of format "n" where n represents the next state */
	/* (except for the rightmost column). */
	/* Cells may also be of format "_(x,y)" where x represents an action */
	/* to perform and y represents the next state. */
	/*                                                                   */
	/* This format limits each table to 16 states each and to 15 actions. */
	/*                                                                   */
	/*********************************************************************/
	/* Definitions and type for levels state tables */
	/*********************************************************************/
	private static final int IMPTABLEVELS_COLUMNS = _B + 2;

	private static final int IMPTABLEVELS_RES = IMPTABLEVELS_COLUMNS - 1;
	/*********************************************************************/
	/*                                                                   */
	/* LEVELS STATE TABLES */
	/*                                                                   */
	/* In all levels state tables, */
	/* - state 0 is the initial state */
	/* - the Res column is the increment to add to the text level */
	/* for this property sequence. */
	/*                                                                   */
	/* The impact arrays for each table of a pair map the local action */
	/* numbers of the table to the total list of actions. For instance, */
	/* action 2 in a given table corresponds to the action number which */
	/* appears in entry [2] of the impact array for that table. */
	/* The first entry of all impact arrays must be 0. */
	/*                                                                   */
	/* Action 1: init conditional sequence */
	/* 2: prepend conditional sequence to current sequence */
	/* 3: set ON sequence to new level - 1 */
	/* 4: init EN/AN/ON sequence */
	/* 5: fix EN/AN/ON sequence followed by R */
	/* 6: set previous level sequence to level 2 */
	/*                                                                   */
	/* Notes: */
	/* 1) These tables are used in processPropertySeq(). The input */
	/* is property sequences as determined by resolveImplicitLevels. */
	/* 2) Most such property sequences are processed immediately */
	/* (levels are assigned). */
	/* 3) However, some sequences cannot be assigned a final level till */
	/* one or more following sequences are received. For instance, */
	/* ON following an R sequence within an even-level paragraph. */
	/* If the following sequence is R, the ON sequence will be */
	/* assigned basic run level+1, and so will the R sequence. */
	/* 4) S is generally handled like ON, since its level will be fixed */
	/* to paragraph level in adjustWSLevels(). */
	/*                                                                   */

	private static final byte impTabL_DEFAULT[][] = /* Even paragraph level */
			/*
			 * In this table, conditional sequences receive the lower possible level until
			 * proven otherwise.
			 */
			{
					/* L, R, EN, AN, ON, S, B, Res */
					/* 0 : init */ { 0, 1, 0, 2, 0, 0, 0, 0 }, /* 1 : R */ { 0, 1, 3, 3, 0x14, 0x14, 0, 1 },
					/* 2 : AN */ { 0, 1, 0, 2, 0x15, 0x15, 0, 2 }, /* 3 : R+EN/AN */ { 0, 1, 3, 3, 0x14, 0x14, 0, 2 },
					/* 4 : R+ON */ { 0, 0x21, 0x33, 0x33, 4, 4, 0, 0 },
					/* 5 : AN+ON */ { 0, 0x21, 0, 0x32, 5, 5, 0, 0 } };

	private static final byte impTabR_DEFAULT[][] = /* Odd paragraph level */
			/*
			 * In this table, conditional sequences receive the lower possible level until
			 * proven otherwise.
			 */
			{
					/* L, R, EN, AN, ON, S, B, Res */
					/* 0 : init */ { 1, 0, 2, 2, 0, 0, 0, 0 }, /* 1 : L */ { 1, 0, 1, 3, 0x14, 0x14, 0, 1 },
					/* 2 : EN/AN */ { 1, 0, 2, 2, 0, 0, 0, 1 }, /* 3 : L+AN */ { 1, 0, 1, 3, 5, 5, 0, 1 },
					/* 4 : L+ON */ { 0x21, 0, 0x21, 3, 4, 4, 0, 0 }, /* 5 : L+AN+ON */ { 1, 0, 1, 3, 5, 5, 0, 0 } };

	private static final short[] impAct0 = { 0, 1, 2, 3, 4 };

	private static final ImpTabPair impTab_DEFAULT = new ImpTabPair(impTabL_DEFAULT, impTabR_DEFAULT, impAct0, impAct0);

	private static final byte impTabL_NUMBERS_SPECIAL[][] = { /* Even paragraph level */
			/*
			 * In this table, conditional sequences receive the lower possible level until
			 * proven otherwise.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 0, 2, 0x11, 0x11, 0, 0, 0, 0 }, /* 1 : L+EN/AN */ { 0, 0x42, 1, 1, 0, 0, 0, 0 },
			/* 2 : R */ { 0, 2, 4, 4, 0x13, 0x13, 0, 1 }, /* 3 : R+ON */ { 0, 0x22, 0x34, 0x34, 3, 3, 0, 0 },
			/* 4 : R+EN/AN */ { 0, 2, 4, 4, 0x13, 0x13, 0, 2 } };

	private static final ImpTabPair impTab_NUMBERS_SPECIAL = new ImpTabPair(impTabL_NUMBERS_SPECIAL, impTabR_DEFAULT,
			impAct0, impAct0);

	private static final byte impTabL_GROUP_NUMBERS_WITH_R[][] = {
			/*
			 * In this table, EN/AN+ON sequences receive levels as if associated with R
			 * until proven that there is L or sor/eor on both sides. AN is handled like EN.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 init */ { 0, 3, 0x11, 0x11, 0, 0, 0, 0 }, /* 1 EN/AN */ { 0x20, 3, 1, 1, 2, 0x20, 0x20, 2 },
			/* 2 EN/AN+ON */ { 0x20, 3, 1, 1, 2, 0x20, 0x20, 1 }, /* 3 R */ { 0, 3, 5, 5, 0x14, 0, 0, 1 },
			/* 4 R+ON */ { 0x20, 3, 5, 5, 4, 0x20, 0x20, 1 }, /* 5 R+EN/AN */ { 0, 3, 5, 5, 0x14, 0, 0, 2 } };
	private static final byte impTabR_GROUP_NUMBERS_WITH_R[][] = {
			/*
			 * In this table, EN/AN+ON sequences receive levels as if associated with R
			 * until proven that there is L on both sides. AN is handled like EN.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 init */ { 2, 0, 1, 1, 0, 0, 0, 0 }, /* 1 EN/AN */ { 2, 0, 1, 1, 0, 0, 0, 1 },
			/* 2 L */ { 2, 0, 0x14, 0x14, 0x13, 0, 0, 1 }, /* 3 L+ON */ { 0x22, 0, 4, 4, 3, 0, 0, 0 },
			/* 4 L+EN/AN */ { 0x22, 0, 4, 4, 3, 0, 0, 1 } };
	private static final ImpTabPair impTab_GROUP_NUMBERS_WITH_R = new ImpTabPair(impTabL_GROUP_NUMBERS_WITH_R,
			impTabR_GROUP_NUMBERS_WITH_R, impAct0, impAct0);

	private static final byte impTabL_INVERSE_NUMBERS_AS_L[][] = {
			/*
			 * This table is identical to the Default LTR table except that EN and AN are
			 * handled like L.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 0, 1, 0, 0, 0, 0, 0, 0 }, /* 1 : R */ { 0, 1, 0, 0, 0x14, 0x14, 0, 1 },
			/* 2 : AN */ { 0, 1, 0, 0, 0x15, 0x15, 0, 2 }, /* 3 : R+EN/AN */ { 0, 1, 0, 0, 0x14, 0x14, 0, 2 },
			/* 4 : R+ON */ { 0x20, 1, 0x20, 0x20, 4, 4, 0x20, 1 },
			/* 5 : AN+ON */ { 0x20, 1, 0x20, 0x20, 5, 5, 0x20, 1 } };

	private static final byte impTabR_INVERSE_NUMBERS_AS_L[][] = {
			/*
			 * This table is identical to the Default RTL table except that EN and AN are
			 * handled like L.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 1, 0, 1, 1, 0, 0, 0, 0 }, /* 1 : L */ { 1, 0, 1, 1, 0x14, 0x14, 0, 1 },
			/* 2 : EN/AN */ { 1, 0, 1, 1, 0, 0, 0, 1 }, /* 3 : L+AN */ { 1, 0, 1, 1, 5, 5, 0, 1 },
			/* 4 : L+ON */ { 0x21, 0, 0x21, 0x21, 4, 4, 0, 0 }, /* 5 : L+AN+ON */ { 1, 0, 1, 1, 5, 5, 0, 0 } };

	private static final ImpTabPair impTab_INVERSE_NUMBERS_AS_L = new ImpTabPair(impTabL_INVERSE_NUMBERS_AS_L,
			impTabR_INVERSE_NUMBERS_AS_L, impAct0, impAct0);

	private static final byte impTabR_INVERSE_LIKE_DIRECT[][] = { /* Odd paragraph level */
			/*
			 * In this table, conditional sequences receive the lower possible level until
			 * proven otherwise.
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 1, 0, 2, 2, 0, 0, 0, 0 }, /* 1 : L */ { 1, 0, 1, 2, 0x13, 0x13, 0, 1 },
			/* 2 : EN/AN */ { 1, 0, 2, 2, 0, 0, 0, 1 }, /* 3 : L+ON */ { 0x21, 0x30, 6, 4, 3, 3, 0x30, 0 },
			/* 4 : L+ON+AN */ { 0x21, 0x30, 6, 4, 5, 5, 0x30, 3 },
			/* 5 : L+AN+ON */ { 0x21, 0x30, 6, 4, 5, 5, 0x30, 2 },
			/* 6 : L+ON+EN */ { 0x21, 0x30, 6, 4, 3, 3, 0x30, 1 } };

	private static final short[] impAct1 = { 0, 1, 13, 14 };

	private static final ImpTabPair impTab_INVERSE_LIKE_DIRECT = new ImpTabPair(impTabL_DEFAULT,
			impTabR_INVERSE_LIKE_DIRECT, impAct0, impAct1);
	private static final byte impTabL_INVERSE_LIKE_DIRECT_WITH_MARKS[][] = {
			/*
			 * The case handled in this table is (visually): R EN L
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 0, 0x63, 0, 1, 0, 0, 0, 0 }, /* 1 : L+AN */ { 0, 0x63, 0, 1, 0x12, 0x30, 0, 4 },
			/* 2 : L+AN+ON */ { 0x20, 0x63, 0x20, 1, 2, 0x30, 0x20, 3 },
			/* 3 : R */ { 0, 0x63, 0x55, 0x56, 0x14, 0x30, 0, 3 },
			/* 4 : R+ON */ { 0x30, 0x43, 0x55, 0x56, 4, 0x30, 0x30, 3 },
			/* 5 : R+EN */ { 0x30, 0x43, 5, 0x56, 0x14, 0x30, 0x30, 4 },
			/* 6 : R+AN */ { 0x30, 0x43, 0x55, 6, 0x14, 0x30, 0x30, 4 } };

	private static final byte impTabR_INVERSE_LIKE_DIRECT_WITH_MARKS[][] = {
			/*
			 * The cases handled in this table are (visually): R EN L R L AN L
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 0x13, 0, 1, 1, 0, 0, 0, 0 }, /* 1 : R+EN/AN */ { 0x23, 0, 1, 1, 2, 0x40, 0, 1 },
			/* 2 : R+EN/AN+ON */ { 0x23, 0, 1, 1, 2, 0x40, 0, 0 }, /* 3 : L */ { 3, 0, 3, 0x36, 0x14, 0x40, 0, 1 },
			/* 4 : L+ON */ { 0x53, 0x40, 5, 0x36, 4, 0x40, 0x40, 0 },
			/* 5 : L+ON+EN */ { 0x53, 0x40, 5, 0x36, 4, 0x40, 0x40, 1 },
			/* 6 : L+AN */ { 0x53, 0x40, 6, 6, 4, 0x40, 0x40, 3 } };

	private static final short[] impAct2 = { 0, 1, 2, 5, 6, 7, 8 };
	private static final short[] impAct3 = { 0, 1, 9, 10, 11, 12 };

	private static final ImpTabPair impTab_INVERSE_LIKE_DIRECT_WITH_MARKS = new ImpTabPair(
			impTabL_INVERSE_LIKE_DIRECT_WITH_MARKS, impTabR_INVERSE_LIKE_DIRECT_WITH_MARKS, impAct2, impAct3);

	private static final ImpTabPair impTab_INVERSE_FOR_NUMBERS_SPECIAL = new ImpTabPair(impTabL_NUMBERS_SPECIAL,
			impTabR_INVERSE_LIKE_DIRECT, impAct0, impAct1);

	private static final byte impTabL_INVERSE_FOR_NUMBERS_SPECIAL_WITH_MARKS[][] = {
			/*
			 * The case handled in this table is (visually): R EN L
			 */
			/* L, R, EN, AN, ON, S, B, Res */
			/* 0 : init */ { 0, 0x62, 1, 1, 0, 0, 0, 0 }, /* 1 : L+EN/AN */ { 0, 0x62, 1, 1, 0, 0x30, 0, 4 },
			/* 2 : R */ { 0, 0x62, 0x54, 0x54, 0x13, 0x30, 0, 3 },
			/* 3 : R+ON */ { 0x30, 0x42, 0x54, 0x54, 3, 0x30, 0x30, 3 },
			/* 4 : R+EN/AN */ { 0x30, 0x42, 4, 4, 0x13, 0x30, 0x30, 4 } };

	private static final ImpTabPair impTab_INVERSE_FOR_NUMBERS_SPECIAL_WITH_MARKS = new ImpTabPair(
			impTabL_INVERSE_FOR_NUMBERS_SPECIAL_WITH_MARKS, impTabR_INVERSE_LIKE_DIRECT_WITH_MARKS, impAct2, impAct3);

	static final int FIRSTALLOC = 10;

	/**
	 * Constant indicating that the base direction depends on the first strong
	 * directional character in the text according to the Unicode Bidirectional
	 * Algorithm. If no strong directional character is present, the base direction
	 * is right-to-left.
	 *
	 * @stable ICU 3.8
	 */
	public static final int DIRECTION_DEFAULT_RIGHT_TO_LEFT = LEVEL_DEFAULT_RTL;

	static final byte DirFromStrong(byte strong) {
		return strong == L ? L : R;
	}

	/*
	 * Sometimes, bit values are more appropriate to deal with directionality
	 * properties. Abbreviations in these method names refer to names used in the
	 * Bidi algorithm.
	 */
	static int DirPropFlag(byte dir) {
		return (1 << dir);
	}

	static final int DirPropFlagE(byte level) {
		return DirPropFlagE[level & 1];
	}

	static final int DirPropFlagLR(byte level) {
		return DirPropFlagLR[level & 1];
	}

	static final int DirPropFlagO(byte level) {
		return DirPropFlagO[level & 1];
	}

	private static short GetAction(byte cell) {
		return (short) (cell >> 4);
	}

	private static short GetActionProps(short cell) {
		return (short) (cell >> 5);
	}

	/*
	 * the dirProp's L and R are defined to 0 and 1 values in
	 * UCharacterDirection.java
	 */
	private static byte GetLRFromLevel(byte level) {
		return (byte) (level & 1);
	}

	private static short GetState(byte cell) {
		return (short) (cell & 0x0f);
	}

	private static short GetStateProps(short cell) {
		return (short) (cell & 0x1f);
	}

	static boolean IsBidiControlChar(int c) {
		/*
		 * check for range 0x200c to 0x200f (ZWNJ, ZWJ, LRM, RLM) or 0x202a to 0x202e
		 * (LRE, RLE, PDF, LRO, RLO)
		 */
		return (((c & 0xfffffffc) == 0x200c) || ((c >= 0x202a) && (c <= 0x202e)) || ((c >= 0x2066) && (c <= 0x2069)));
	}

	private static boolean IsDefaultLevel(byte level) {
		return ((level & LEVEL_DEFAULT_LTR) == LEVEL_DEFAULT_LTR);
	}

	static final byte NoOverride(byte level) {
		return (byte) (level & ~LEVEL_OVERRIDE);
	}

	/**
	 * This is a convenience method that does not use a <code>Bidi</code> object. It
	 * is intended to be used for when an application has determined the levels of
	 * objects (character sequences) and just needs to have them reordered (L2).
	 * This is equivalent to using <code>getVisualMap()</code> on a
	 * <code>Bidi</code> object.
	 *
	 * @param levels is an array of levels that have been determined by the
	 *               application.
	 *
	 * @return an array of <code>levels.length</code> indexes which will reflect the
	 *         reordering of the characters.
	 *         <p>
	 *         The index map will result in
	 *         <code>indexMap[visualIndex]==logicalIndex</code>, where
	 *         <code>indexMap</code> represents the returned array.
	 *
	 * @stable ICU 3.8
	 */
	private static int[] reorderVisual(byte[] levels) {
		return BidiLine.reorderVisual(levels);
	}

	/**
	 * Reorder the objects in the array into visual order based on their levels.
	 * This is a utility method to use when you have a collection of objects
	 * representing runs of text in logical order, each run containing text at a
	 * single level. The elements at <code>index</code> from
	 * <code>objectStart</code> up to <code>objectStart + count</code> in the
	 * objects array will be reordered into visual order assuming each run of text
	 * has the level indicated by the corresponding element in the levels array (at
	 * <code>index - objectStart + levelStart</code>).
	 *
	 * @param levels      an array representing the bidi level of each object
	 * @param levelStart  the start position in the levels array
	 * @param objects     the array of objects to be reordered into visual order
	 * @param objectStart the start position in the objects array
	 * @param count       the number of objects to reorder
	 * @stable ICU 3.8
	 */
	public static void reorderVisually(byte[] levels, int levelStart, Object[] objects, int objectStart, int count) {
		// for backward compatibility
		if (0 > levelStart || levels.length <= levelStart) {
			throw new IllegalArgumentException(
					"Value levelStart " + levelStart + " is out of range 0 to " + (levels.length - 1));
		}
		if (0 > objectStart || objects.length <= objectStart) {
			throw new IllegalArgumentException(
					"Value objectStart " + objectStart + " is out of range 0 to " + (objects.length - 1));
		}
		if (0 > count || objects.length < (objectStart + count)) {
			throw new IllegalArgumentException("Value count " + count + " is less than zero, or objectStart + count"
					+ " is beyond objects length " + objects.length);
		}

		byte[] reorderLevels = new byte[count];
		System.arraycopy(levels, levelStart, reorderLevels, 0, count);
		int[] indexMap = reorderVisual(reorderLevels);
		Object[] temp = new Object[count];
		System.arraycopy(objects, objectStart, temp, 0, count);
		for (int i = 0; i < count; ++i) {
			objects[objectStart + i] = temp[indexMap[i]];
		}
	}

	/**
	 * Return true if the specified text requires bidi analysis. If this returns
	 * false, the text will display left-to-right. Clients can then avoid
	 * constructing a Bidi object. Text in the Arabic Presentation Forms area of
	 * Unicode is presumed to already be shaped and ordered for display, and so will
	 * not cause this method to return true.
	 *
	 * @param text  the text containing the characters to test
	 * @param start the start of the range of characters to test
	 * @param limit the limit of the range of characters to test
	 *
	 * @return true if the range of characters requires bidi analysis
	 *
	 * @stable ICU 3.8
	 */
	public static boolean requiresBidi(char[] text, int start, int limit) {
		final int RTLMask = (1 << R | 1 << AL | 1 << RLE | 1 << RLO | 1 << AN);

		if (0 > start || start > limit || limit > text.length) {
			throw new IllegalArgumentException("Value start " + start + " is out of range 0 to " + limit + ", or limit "
					+ limit + " is beyond the text length " + text.length);
		}

		for (int i = start; i < limit; ++i) {
			if (Character.isHighSurrogate(text[i]) && i < (limit - 1) && Character.isLowSurrogate(text[i + 1])) {
				if (((1 << UCharacter.getDirection(Character.codePointAt(text, i))) & RTLMask) != 0) {
					return true;
				}
			} else if (((1 << UCharacter.getDirection(text[i])) & RTLMask) != 0) {
				return true;
			}
		}

		return false;
	}

	/*
	 * reference to parent paragraph object (reference to self if this object is a
	 * paragraph object); set to null in a newly opened object; set to a real value
	 * after a successful execution of setPara or setLine
	 */
	BidiBase paraBidi;

	/* perform (P2)..(P3) ------------------------------------------------------- */

	final UBiDiProps bdp;

	/* character array representing the current text */
	char[] text;
	/* length of the current text */
	int originalLength;
	/*
	 * if the option OPTION_STREAMING is set, this is the length of text actually
	 * processed by <code>setPara</code>, which may be shorter than the original
	 * length. Otherwise, it is identical to the original length.
	 */
	public int length;
	/*
	 * if option OPTION_REMOVE_CONTROLS is set, and/or Bidi marks are allowed to be
	 * inserted in one of the reordering modes, the length of the result string may
	 * be different from the processed length.
	 */
	int resultLength;

	/* indicators for whether memory may be allocated after construction */
	boolean mayAllocateText;

	boolean mayAllocateRuns;

	/* Functions for handling paired brackets ----------------------------------- */

	/*
	 * In the isoRuns array, the first entry is used for text outside of any isolate
	 * sequence. Higher entries are used for each more deeply nested isolate
	 * sequence. isoRunLast is the index of the last used entry. The openings array
	 * is used to note the data of opening brackets not yet matched by a closing
	 * bracket, or matched but still susceptible to change level. Each isoRun entry
	 * contains the index of the first and one-after-last openings entries for
	 * pending opening brackets it contains. The next openings entry to use is the
	 * one-after-last of the most deeply nested isoRun entry. isoRun entries also
	 * contain their current embedding level and the last encountered strong
	 * character, since these will be needed to resolve the level of paired
	 * brackets.
	 */

	/* arrays with one value per text-character */
	byte[] dirPropsMemory = new byte[1];

	byte[] levelsMemory = new byte[1];

	byte[] dirProps;

	byte[] levels;

	/* are we performing an approximation of the "inverse Bidi" algorithm? */
	boolean isInverse;

	/* are we using the basic algorithm or its variation? */
	int reorderingMode;

	/* bitmask for reordering options */
	int reorderingOptions;

	/* must block separators receive level 0? */
	boolean orderParagraphsLTR;

	/* the paragraph level */
	byte paraLevel;

	/* perform (X1)..(X9) ------------------------------------------------------- */

	/* original paraLevel when contextual */
	/* must be one of DEFAULT_xxx or 0 if not contextual */
	byte defaultParaLevel;

	ImpTabPair impTabPair; /* reference to levels state table pair */

	/* the overall paragraph or line directionality */
	byte direction;

	/*********************************************************************/
	/* The Properties state machine table */
	/*********************************************************************/
	/*                                                                   */
	/* All table cells are 8 bits: */
	/* bits 0..4: next state */
	/* bits 5..7: action to perform (if > 0) */
	/*                                                                   */
	/* Cells may be of format "n" where n represents the next state */
	/* (except for the rightmost column). */
	/* Cells may also be of format "_(x,y)" where x represents an action */
	/* to perform and y represents the next state. */
	/*                                                                   */
	/*********************************************************************/

	/* flags is a bit set for which directional properties are in the text */
	int flags;
	/* lastArabicPos is index to the last AL in the text, -1 if none */
	int lastArabicPos;

	/* characters after trailingWSStart are WS and are */
	/* implicitly at the paraLevel (rule (L1)) - levels may not reflect that */
	int trailingWSStart;

	/* fields for paragraph handling, set in getDirProps() */
	int paraCount;

	int[] paras_limit = new int[SIMPLE_PARAS_COUNT];
	byte[] paras_level = new byte[SIMPLE_PARAS_COUNT];
	/* fields for line reordering */
	int runCount; /* ==-1: runs not set up yet */
	BidiRun[] runsMemory = new BidiRun[0];
	BidiRun[] runs;
	/* for non-mixed text, we only need a tiny array of runs (no allocation) */
	BidiRun[] simpleRuns = { new BidiRun() };
	/* fields for managing isolate sequences */
	Isolate[] isolates;
	/* maximum or current nesting depth of isolate sequences */
	/*
	 * Within resolveExplicitLevels() and checkExplicitLevels(), this is the maximal
	 * nesting encountered. Within resolveImplicitLevels(), this is the index of the
	 * current isolates stack entry.
	 */
	int isolateCount;

	/* mapping of runs in logical order to visual order */
	int[] logicalToVisualRunsMap;

	/* flag to indicate that the map has been updated */
	boolean isGoodLogicalToVisualRunsMap;
	/* for inverse Bidi with insertion of directional marks */
	InsertPoints insertPoints = new InsertPoints();

	/* for option OPTION_REMOVE_CONTROLS */
	int controlCount;

	/**
	 * Create Bidi from the given text, embedding, and direction information. The
	 * embeddings array may be null. If present, the values represent embedding
	 * level information. Negative values from -1 to -61 indicate overrides at the
	 * absolute value of the level. Positive values from 1 to 61 indicate
	 * embeddings. Where values are zero, the base embedding level as determined by
	 * the base direction is assumed.
	 * <p>
	 *
	 * Note: this constructor calls setPara() internally.
	 *
	 * @param text            an array containing the paragraph of text to process.
	 * @param textStart       the index into the text array of the start of the
	 *                        paragraph.
	 * @param embeddings      an array containing embedding values for each
	 *                        character in the paragraph. This can be null, in which
	 *                        case it is assumed that there is no external embedding
	 *                        information.
	 * @param embStart        the index into the embedding array of the start of the
	 *                        paragraph.
	 * @param paragraphLength the length of the paragraph in the text and embeddings
	 *                        arrays.
	 * @param flags           a collection of flags that control the algorithm. The
	 *                        algorithm understands the flags
	 *                        DIRECTION_LEFT_TO_RIGHT, DIRECTION_RIGHT_TO_LEFT,
	 *                        DIRECTION_DEFAULT_LEFT_TO_RIGHT, and
	 *                        DIRECTION_DEFAULT_RIGHT_TO_LEFT. Other values are
	 *                        reserved.
	 *
	 * @throws IllegalArgumentException if the values in embeddings are not within
	 *                                  the allowed range
	 *
	 * @see #DIRECTION_LEFT_TO_RIGHT
	 * @see #DIRECTION_RIGHT_TO_LEFT
	 * @see #DIRECTION_DEFAULT_LEFT_TO_RIGHT
	 * @see #DIRECTION_DEFAULT_RIGHT_TO_LEFT
	 * @stable ICU 3.8
	 */
	public BidiBase(char[] text, int textStart, byte[] embeddings, int embStart, int paragraphLength, int flags) {
		this(0, 0);
		byte paraLvl;
		switch (flags) {
		case Bidi.DIRECTION_LEFT_TO_RIGHT:
		default:
			paraLvl = LTR;
			break;
		case Bidi.DIRECTION_RIGHT_TO_LEFT:
			paraLvl = RTL;
			break;
		case Bidi.DIRECTION_DEFAULT_LEFT_TO_RIGHT:
			paraLvl = LEVEL_DEFAULT_LTR;
			break;
		case Bidi.DIRECTION_DEFAULT_RIGHT_TO_LEFT:
			paraLvl = LEVEL_DEFAULT_RTL;
			break;
		}
		byte[] paraEmbeddings;
		if (embeddings == null) {
			paraEmbeddings = null;
		} else {
			paraEmbeddings = new byte[paragraphLength];
			byte lev;
			for (int i = 0; i < paragraphLength; i++) {
				lev = embeddings[i + embStart];
				if (lev < 0) {
					lev = (byte) ((-lev) | LEVEL_OVERRIDE);
				} else if (lev == 0) {
					lev = paraLvl;
					if (paraLvl > MAX_EXPLICIT_LEVEL) {
						lev &= 1;
					}
				}
				paraEmbeddings[i] = lev;
			}
		}

		char[] paraText = new char[paragraphLength];
		System.arraycopy(text, textStart, paraText, 0, paragraphLength);
		setPara(paraText, paraLvl, paraEmbeddings);
	}

	/**
	 * Allocate a <code>Bidi</code> object with preallocated memory for internal
	 * structures. This method provides a <code>Bidi</code> object like the default
	 * constructor but it also preallocates memory for internal structures according
	 * to the sizings supplied by the caller.
	 * <p>
	 * The preallocation can be limited to some of the internal memory by setting
	 * some values to 0 here. That means that if, e.g., <code>maxRunCount</code>
	 * cannot be reasonably predetermined and should not be set to
	 * <code>maxLength</code> (the only failproof value) to avoid wasting memory,
	 * then <code>maxRunCount</code> could be set to 0 here and the internal
	 * structures that are associated with it will be allocated on demand, just like
	 * with the default constructor.
	 *
	 * @param maxLength   is the maximum text or line length that internal memory
	 *                    will be preallocated for. An attempt to associate this
	 *                    object with a longer text will fail, unless this value is
	 *                    0, which leaves the allocation up to the implementation.
	 *
	 * @param maxRunCount is the maximum anticipated number of same-level runs that
	 *                    internal memory will be preallocated for. An attempt to
	 *                    access visual runs on an object that was not preallocated
	 *                    for as many runs as the text was actually resolved to will
	 *                    fail, unless this value is 0, which leaves the allocation
	 *                    up to the implementation.<br>
	 *                    <br>
	 *                    The number of runs depends on the actual text and maybe
	 *                    anywhere between 1 and <code>maxLength</code>. It is
	 *                    typically small.
	 *
	 * @throws IllegalArgumentException if maxLength or maxRunCount is less than 0
	 * @stable ICU 3.8
	 */
	public BidiBase(int maxLength, int maxRunCount) {
		/* check the argument values */
		if (maxLength < 0 || maxRunCount < 0) {
			throw new IllegalArgumentException();
		}

		/*
		 * reset the object, all reference variables null, all flags false, all sizes 0.
		 * In fact, we don't need to do anything, since class members are initialized as
		 * zero when an instance is created.
		 */
		/*
		 * mayAllocateText = false; mayAllocateRuns = false; orderParagraphsLTR = false;
		 * paraCount = 0; runCount = 0; trailingWSStart = 0; flags = 0; paraLevel = 0;
		 * defaultParaLevel = 0; direction = 0;
		 */
		/* get Bidi properties */
		bdp = UBiDiProps.INSTANCE;

		/* allocate memory for arrays as requested */
		if (maxLength > 0) {
			getInitialDirPropsMemory(maxLength);
			getInitialLevelsMemory(maxLength);
		} else {
			mayAllocateText = true;
		}

		if (maxRunCount > 0) {
			// if maxRunCount == 1, use simpleRuns[]
			if (maxRunCount > 1) {
				getInitialRunsMemory(maxRunCount);
			}
		} else {
			mayAllocateRuns = true;
		}
	}

	/*
	 * param pos: position where to insert param flag: one of LRM_BEFORE, LRM_AFTER,
	 * RLM_BEFORE, RLM_AFTER
	 */
	private void addPoint(int pos, int flag) {
		Point point = new Point();

		int len = insertPoints.points.length;
		if (len == 0) {
			insertPoints.points = new Point[FIRSTALLOC];
			len = FIRSTALLOC;
		}
		if (insertPoints.size >= len) { /* no room for new point */
			Point[] savePoints = insertPoints.points;
			insertPoints.points = new Point[len * 2];
			System.arraycopy(savePoints, 0, insertPoints.points, 0, len);
		}
		point.pos = pos;
		point.flag = flag;
		insertPoints.points[insertPoints.size] = point;
		insertPoints.size++;
	}

	/*
	 * Reset the embedding levels for some non-graphic characters (L1). This method
	 * also sets appropriate levels for BN, and explicit embedding types that are
	 * supposed to have been removed from the paragraph in (X9).
	 */
	private void adjustWSLevels() {
		int i;

		if ((flags & MASK_WS) != 0) {
			int flag;
			i = trailingWSStart;
			while (i > 0) {
				/* reset a sequence of WS/BN before eop and B/S to the paragraph paraLevel */
				while (i > 0 && ((flag = DirPropFlag(dirProps[--i])) & MASK_WS) != 0) {
					if (orderParagraphsLTR && (flag & DirPropFlag(B)) != 0) {
						levels[i] = 0;
					} else {
						levels[i] = GetParaLevelAt(i);
					}
				}

				/*
				 * reset BN to the next character's paraLevel until B/S, which restarts above
				 * loop
				 */
				/* here, i+1 is guaranteed to be <length */
				while (i > 0) {
					flag = DirPropFlag(dirProps[--i]);
					if ((flag & MASK_BN_EXPLICIT) != 0) {
						levels[i] = levels[i + 1];
					} else if (orderParagraphsLTR && (flag & DirPropFlag(B)) != 0) {
						levels[i] = 0;
						break;
					} else if ((flag & MASK_B_S) != 0) {
						levels[i] = GetParaLevelAt(i);
						break;
					}
				}
			}
		}
	}

	/**
	 * Return true if the base direction is left-to-right
	 *
	 * @return true if the base direction is left-to-right
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @stable ICU 3.8
	 */
	public boolean baseIsLeftToRight() {
		return (getParaLevel() == LTR);
	}

	private int Bidi_Abs(int x) {
		return x >= 0 ? x : -x;
	}

	private int Bidi_Min(int x, int y) {
		return x < y ? x : y;
	}

	/* newly found opening bracket: create an openings entry */
	private void bracketAddOpening(BracketData bd, char match, int position) {
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		Opening pOpening;
		if (pLastIsoRun.limit >= bd.openings.length) { /* no available new entry */
			Opening[] saveOpenings = bd.openings;
			int count;
			try {
				count = bd.openings.length;
				bd.openings = new Opening[count * 2];
			} catch (Exception e) {
				throw new OutOfMemoryError("Failed to allocate memory for openings");
			}
			System.arraycopy(saveOpenings, 0, bd.openings, 0, count);
		}
		pOpening = bd.openings[pLastIsoRun.limit];
		if (pOpening == null)
			pOpening = bd.openings[pLastIsoRun.limit] = new Opening();
		pOpening.position = position;
		pOpening.match = match;
		pOpening.contextDir = pLastIsoRun.contextDir;
		pOpening.contextPos = pLastIsoRun.contextPos;
		pOpening.flags = 0;
		pLastIsoRun.limit++;
	}

	private void bracketInit(BracketData bd) {
		bd.isoRunLast = 0;
		bd.isoRuns[0] = new IsoRun();
		bd.isoRuns[0].start = 0;
		bd.isoRuns[0].limit = 0;
		bd.isoRuns[0].level = GetParaLevelAt(0);
		bd.isoRuns[0].lastStrong = bd.isoRuns[0].lastBase = bd.isoRuns[0].contextDir = (byte) (GetParaLevelAt(0) & 1);
		bd.isoRuns[0].contextPos = 0;
		bd.openings = new Opening[SIMPLE_PARAS_COUNT];
		bd.isNumbersSpecial = reorderingMode == REORDER_NUMBERS_SPECIAL
				|| reorderingMode == REORDER_INVERSE_FOR_NUMBERS_SPECIAL;
	}

	/* paragraph boundary */
	private void bracketProcessB(BracketData bd, byte level) {
		bd.isoRunLast = 0;
		bd.isoRuns[0].limit = 0;
		bd.isoRuns[0].level = level;
		bd.isoRuns[0].lastStrong = bd.isoRuns[0].lastBase = bd.isoRuns[0].contextDir = (byte) (level & 1);
		bd.isoRuns[0].contextPos = 0;
	}

	/* LRE, LRO, RLE, RLO, PDF */
	private void bracketProcessBoundary(BracketData bd, int lastCcPos, byte contextLevel, byte embeddingLevel) {
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		if ((DirPropFlag(dirProps[lastCcPos]) & MASK_ISO) != 0) /* after an isolate */
			return;
		if (NoOverride(embeddingLevel) > NoOverride(contextLevel)) /* not a PDF */
			contextLevel = embeddingLevel;
		pLastIsoRun.limit = pLastIsoRun.start;
		pLastIsoRun.level = embeddingLevel;
		pLastIsoRun.lastStrong = pLastIsoRun.lastBase = pLastIsoRun.contextDir = (byte) (contextLevel & 1);
		pLastIsoRun.contextPos = lastCcPos;
	}

	/* handle strong characters, digits and candidates for closing brackets */
	private void bracketProcessChar(BracketData bd, int position) {
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		byte dirProp, newProp;
		byte level;
		dirProp = dirProps[position];
		if (dirProp == ON) {
			char c, match;
			int idx;
			/*
			 * First see if it is a matching closing bracket. Hopefully, this is more
			 * efficient than checking if it is a closing bracket at all
			 */
			c = text[position];
			for (idx = pLastIsoRun.limit - 1; idx >= pLastIsoRun.start; idx--) {
				if (bd.openings[idx].match != c)
					continue;
				/* We have a match */
				newProp = bracketProcessClosing(bd, idx, position);
				if (newProp == ON) { /* N0d */
					c = 0; /* prevent handling as an opening */
					break;
				}
				pLastIsoRun.lastBase = ON;
				pLastIsoRun.contextDir = newProp;
				pLastIsoRun.contextPos = position;
				level = levels[position];
				if ((level & LEVEL_OVERRIDE) != 0) { /* X4, X5 */
					short flag;
					int i;
					newProp = (byte) (level & 1);
					pLastIsoRun.lastStrong = newProp;
					flag = (short) DirPropFlag(newProp);
					for (i = pLastIsoRun.start; i < idx; i++)
						bd.openings[i].flags |= flag;
					/* matching brackets are not overridden by LRO/RLO */
					levels[position] &= ~LEVEL_OVERRIDE;
				}
				/* matching brackets are not overridden by LRO/RLO */
				levels[bd.openings[idx].position] &= ~LEVEL_OVERRIDE;
				return;
			}
			/*
			 * We get here only if the ON character is not a matching closing bracket or it
			 * is a case of N0d
			 */
			/* Now see if it is an opening bracket */
			if (c != 0) {
				match = (char) UCharacter.getBidiPairedBracket(c); /* get the matching char */
			} else {
				match = 0;
			}
			if (match != c && /* has a matching char */
					UCharacter.getIntPropertyValue(c, BIDI_PAIRED_BRACKET_TYPE) ==
					/* opening bracket */ BidiPairedBracketType.OPEN) {
				/*
				 * special case: process synonyms create an opening entry for each synonym
				 */
				if (match == 0x232A) { /* RIGHT-POINTING ANGLE BRACKET */
					bracketAddOpening(bd, (char) 0x3009, position);
				} else if (match == 0x3009) { /* RIGHT ANGLE BRACKET */
					bracketAddOpening(bd, (char) 0x232A, position);
				}
				bracketAddOpening(bd, match, position);
			}
		}
		level = levels[position];
		if ((level & LEVEL_OVERRIDE) != 0) { /* X4, X5 */
			newProp = (byte) (level & 1);
			if (dirProp != S && dirProp != WS && dirProp != ON)
				dirProps[position] = newProp;
			pLastIsoRun.lastBase = newProp;
			pLastIsoRun.lastStrong = newProp;
			pLastIsoRun.contextDir = newProp;
			pLastIsoRun.contextPos = position;
		} else if (dirProp <= R || dirProp == AL) {
			newProp = DirFromStrong(dirProp);
			pLastIsoRun.lastBase = dirProp;
			pLastIsoRun.lastStrong = dirProp;
			pLastIsoRun.contextDir = newProp;
			pLastIsoRun.contextPos = position;
		} else if (dirProp == EN) {
			pLastIsoRun.lastBase = EN;
			if (pLastIsoRun.lastStrong == L) {
				newProp = L; /* W7 */
				if (!bd.isNumbersSpecial)
					dirProps[position] = ENL;
				pLastIsoRun.contextDir = L;
				pLastIsoRun.contextPos = position;
			} else {
				newProp = R; /* N0 */
				if (pLastIsoRun.lastStrong == AL)
					dirProps[position] = AN; /* W2 */
				else
					dirProps[position] = ENR;
				pLastIsoRun.contextDir = R;
				pLastIsoRun.contextPos = position;
			}
		} else if (dirProp == AN) {
			newProp = R; /* N0 */
			pLastIsoRun.lastBase = AN;
			pLastIsoRun.contextDir = R;
			pLastIsoRun.contextPos = position;
		} else if (dirProp == NSM) {
			/*
			 * if the last real char was ON, change NSM to ON so that it will stay ON even
			 * if the last real char is a bracket which may be changed to L or R
			 */
			newProp = pLastIsoRun.lastBase;
			if (newProp == ON)
				dirProps[position] = newProp;
		} else {
			newProp = dirProp;
			pLastIsoRun.lastBase = dirProp;
		}
		if (newProp <= R || newProp == AL) {
			int i;
			short flag = (short) DirPropFlag(DirFromStrong(newProp));
			for (i = pLastIsoRun.start; i < pLastIsoRun.limit; i++)
				if (position > bd.openings[i].position)
					bd.openings[i].flags |= flag;
		}
	}

	/* process closing bracket; return L or R if N0b or N0c, ON if N0d */
	private byte bracketProcessClosing(BracketData bd, int openIdx, int position) {
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		Opening pOpening, qOpening;
		byte direction;
		boolean stable;
		byte newProp;
		pOpening = bd.openings[openIdx];
		direction = (byte) (pLastIsoRun.level & 1);
		stable = true; /* assume stable until proved otherwise */

		/*
		 * The stable flag is set when brackets are paired and their level is resolved
		 * and cannot be changed by what will be found later in the source string. An
		 * unstable match can occur only when applying N0c, where the resolved level
		 * depends on the preceding context, and this context may be affected by text
		 * occurring later. Example: RTL paragraph containing: abc[(latin) HEBREW] When
		 * the closing parenthesis is encountered, it appears that N0c1 must be applied
		 * since 'abc' sets an opposite direction context and both parentheses receive
		 * level 2. However, when the closing square bracket is processed, N0b applies
		 * because of 'HEBREW' being included within the brackets, thus the square
		 * brackets are treated like R and receive level 1. However, this changes the
		 * preceding context of the opening parenthesis, and it now appears that N0c2
		 * must be applied to the parentheses rather than N0c1.
		 */

		if ((direction == 0 && (pOpening.flags & FOUND_L) > 0)
				|| (direction == 1 && (pOpening.flags & FOUND_R) > 0)) { /* N0b */
			newProp = direction;
		} else if ((pOpening.flags & (FOUND_L | FOUND_R)) != 0) { /* N0c */
			/*
			 * it is stable if there is no preceding text or in conditions too complicated
			 * and not worth checking
			 */
			stable = (openIdx == pLastIsoRun.start);
			if (direction != pOpening.contextDir)
				newProp = pOpening.contextDir; /* N0c1 */
			else
				newProp = direction; /* N0c2 */
		} else {
			/* forget this and any brackets nested within this pair */
			pLastIsoRun.limit = (short) openIdx;
			return ON; /* N0d */
		}
		dirProps[pOpening.position] = newProp;
		dirProps[position] = newProp;
		/* Update nested N0c pairs that may be affected */
		fixN0c(bd, openIdx, pOpening.position, newProp);
		if (stable) {
			pLastIsoRun.limit = (short) openIdx; /* forget any brackets nested within this pair */
			/* remove lower located synonyms if any */
			while (pLastIsoRun.limit > pLastIsoRun.start
					&& bd.openings[pLastIsoRun.limit - 1].position == pOpening.position)
				pLastIsoRun.limit--;
		} else {
			int k;
			pOpening.match = -position;
			/* neutralize lower located synonyms if any */
			k = openIdx - 1;
			while (k >= pLastIsoRun.start && bd.openings[k].position == pOpening.position)
				bd.openings[k--].match = 0;
			/*
			 * neutralize any unmatched opening between the current pair; this will also
			 * neutralize higher located synonyms if any
			 */
			for (k = openIdx + 1; k < pLastIsoRun.limit; k++) {
				qOpening = bd.openings[k];
				if (qOpening.position >= position)
					break;
				if (qOpening.match > 0)
					qOpening.match = 0;
			}
		}
		return newProp;
	}

	/* LRI or RLI */
	private void bracketProcessLRI_RLI(BracketData bd, byte level) {
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		short lastLimit;
		pLastIsoRun.lastBase = ON;
		lastLimit = pLastIsoRun.limit;
		bd.isoRunLast++;
		pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		if (pLastIsoRun == null)
			pLastIsoRun = bd.isoRuns[bd.isoRunLast] = new IsoRun();
		pLastIsoRun.start = pLastIsoRun.limit = lastLimit;
		pLastIsoRun.level = level;
		pLastIsoRun.lastStrong = pLastIsoRun.lastBase = pLastIsoRun.contextDir = (byte) (level & 1);
		pLastIsoRun.contextPos = 0;
	}

	/* PDI */
	private void bracketProcessPDI(BracketData bd) {
		IsoRun pLastIsoRun;
		bd.isoRunLast--;
		pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		pLastIsoRun.lastBase = ON;
	}

	/*
	 * Use a pre-specified embedding levels array:
	 *
	 * Adjust the directional properties for overrides (->LEVEL_OVERRIDE), ignore
	 * all explicit codes (X9), and check all the preset levels.
	 *
	 * Recalculate the flags to have them reflect the real properties after taking
	 * the explicit embeddings into account.
	 */
	private byte checkExplicitLevels() {
		byte dirProp;
		int i;
		int isolateCount = 0;

		this.flags = 0; /* collect all directionalities in the text */
		byte level;
		this.isolateCount = 0;

		for (i = 0; i < length; ++i) {
			if (levels[i] == 0) {
				levels[i] = paraLevel;
			}

			// for backward compatibility
			if (MAX_EXPLICIT_LEVEL < (levels[i] & 0x7f)) {
				if ((levels[i] & LEVEL_OVERRIDE) != 0) {
					levels[i] = (byte) (paraLevel | LEVEL_OVERRIDE);
				} else {
					levels[i] = paraLevel;
				}
			}

			level = levels[i];
			dirProp = dirProps[i];
			if (dirProp == LRI || dirProp == RLI) {
				isolateCount++;
				if (isolateCount > this.isolateCount)
					this.isolateCount = isolateCount;
			} else if (dirProp == PDI) {
				isolateCount--;
			} else if (dirProp == B) {
				isolateCount = 0;
			}
			if ((level & LEVEL_OVERRIDE) != 0) {
				/* keep the override flag in levels[i] but adjust the flags */
				level &= ~LEVEL_OVERRIDE; /* make the range check below simpler */
				flags |= DirPropFlagO(level);
			} else {
				/* set the flags */
				flags |= DirPropFlagE(level) | DirPropFlag(dirProp);
			}
			if ((level < GetParaLevelAt(i) && !((0 == level) && (dirProp == B))) || (MAX_EXPLICIT_LEVEL < level)) {
				/* level out of bounds */
				throw new IllegalArgumentException("level " + level + " out of bounds at " + i);
			}
		}
		if ((flags & MASK_EMBEDDING) != 0) {
			flags |= DirPropFlagLR(paraLevel);
		}
		/* determine if the text is mixed-directional or single-directional */
		return directionFromFlags();
	}

	/*
	 * Check that there are enough entries in the arrays paras_limit and paras_level
	 */
	private void checkParaCount() {
		int[] saveLimits;
		byte[] saveLevels;
		int count = paraCount;
		if (count <= paras_level.length)
			return;
		int oldLength = paras_level.length;
		saveLimits = paras_limit;
		saveLevels = paras_level;
		try {
			paras_limit = new int[count * 2];
			paras_level = new byte[count * 2];
		} catch (Exception e) {
			throw new OutOfMemoryError("Failed to allocate memory for paras");
		}
		System.arraycopy(saveLimits, 0, paras_limit, 0, oldLength);
		System.arraycopy(saveLevels, 0, paras_level, 0, oldLength);
	}

	/**
	 * Get the number of runs. This method may invoke the actual reordering on the
	 * <code>Bidi</code> object, after <code>setPara()</code> may have resolved only
	 * the levels of the text. Therefore, <code>countRuns()</code> may have to
	 * allocate memory, and may throw an exception if it fails to do so.
	 *
	 * @return The number of runs.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 * @stable ICU 3.8
	 */
	public int countRuns() {
		verifyValidParaOrLine();
		BidiLine.getRuns(this);
		return runCount;
	}

	/* determine if the text is mixed-directional or single-directional */
	private byte directionFromFlags() {

		/* if the text contains AN and neutrals, then some neutrals may become RTL */
		if (!((flags & MASK_RTL) != 0 || ((flags & DirPropFlag(AN)) != 0 && (flags & MASK_POSSIBLE_N) != 0))) {
			return LTR;
		} else if ((flags & MASK_LTR) == 0) {
			return RTL;
		} else {
			return MIXED;
		}
	}

	/*
	 * change N0c1 to N0c2 when a preceding bracket is assigned the embedding level
	 */
	private void fixN0c(BracketData bd, int openingIndex, int newPropPosition, byte newProp) {
		/* This function calls itself recursively */
		IsoRun pLastIsoRun = bd.isoRuns[bd.isoRunLast];
		Opening qOpening;
		int k, openingPosition, closingPosition;
		for (k = openingIndex + 1; k < pLastIsoRun.limit; k++) {
			qOpening = bd.openings[k];
			if (qOpening.match >= 0) /* not an N0c match */
				continue;
			if (newPropPosition < qOpening.contextPos)
				break;
			if (newPropPosition >= qOpening.position)
				continue;
			if (newProp == qOpening.contextDir)
				break;
			openingPosition = qOpening.position;
			dirProps[openingPosition] = newProp;
			closingPosition = -(qOpening.match);
			dirProps[closingPosition] = newProp;
			qOpening.match = 0; /* prevent further changes */
			fixN0c(bd, k, openingPosition, newProp);
			fixN0c(bd, k, closingPosition, newProp);
		}
	}

	/**
	 * Return the base level (0 if left-to-right, 1 if right-to-left).
	 *
	 * @return the base level
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @stable ICU 3.8
	 */
	public int getBaseLevel() {
		return getParaLevel();
	}

	/**
	 * Retrieves the Bidi class for a given code point.
	 * <p>
	 * If a <code>BidiClassifier</code> is defined and returns a value other than
	 * <code>CLASS_DEFAULT</code>, that value is used; otherwise the default class
	 * determination mechanism is invoked.
	 * </p>
	 *
	 * @param c The code point to get a Bidi class for.
	 *
	 * @return The Bidi class for the character <code>c</code> that is in effect for
	 *         this <code>Bidi</code> instance.
	 *
	 * @stable ICU 3.8
	 */
	public int getCustomizedClass(int c) {
		int dir;

		dir = bdp.getClass(c);
		if (dir >= CHAR_DIRECTION_COUNT)
			dir = ON;
		return dir;
	}

	/**
	 * Get the directionality of the text.
	 *
	 * @return a value of <code>LTR</code>, <code>RTL</code> or <code>MIXED</code>
	 *         that indicates if the entire text represented by this object is
	 *         unidirectional, and which direction, or if it is mixed-directional.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @see #LTR
	 * @see #RTL
	 * @see #MIXED
	 * @stable ICU 3.8
	 */
	public byte getDirection() {
		verifyValidParaOrLine();
		return direction;
	}

	private void getDirProps() {
		int i = 0, i0, i1;
		flags = 0; /* collect all directionalities in the text */
		int uchar;
		byte dirProp;
		byte defaultParaLevel = 0; /* initialize to avoid compiler warnings */
		boolean isDefaultLevel = IsDefaultLevel(paraLevel);
		/*
		 * for inverse Bidi, the default para level is set to RTL if there is a strong R
		 * or AL character at either end of the text
		 */
		boolean isDefaultLevelInverse = isDefaultLevel && (reorderingMode == REORDER_INVERSE_LIKE_DIRECT
				|| reorderingMode == REORDER_INVERSE_FOR_NUMBERS_SPECIAL);
		lastArabicPos = -1;
		int controlCount = 0;
		boolean removeBidiControls = (reorderingOptions & OPTION_REMOVE_CONTROLS) != 0;

		byte state;
		byte lastStrong = ON; /* for default level & inverse Bidi */
		/*
		 * The following stacks are used to manage isolate sequences. Those sequences
		 * may be nested, but obviously never more deeply than the maximum explicit
		 * embedding level. lastStack is the index of the last used entry in the stack.
		 * A value of -1 means that there is no open isolate sequence. lastStack is
		 * reset to -1 on paragraph boundaries.
		 */
		/*
		 * The following stack contains the position of the initiator of each open
		 * isolate sequence
		 */
		int[] isolateStartStack = new int[MAX_EXPLICIT_LEVEL + 1];
		/*
		 * The following stack contains the last known state before encountering the
		 * initiator of an isolate sequence
		 */
		byte[] previousStateStack = new byte[MAX_EXPLICIT_LEVEL + 1];
		int stackLast = -1;

		if ((reorderingOptions & OPTION_STREAMING) != 0)
			length = 0;
		defaultParaLevel = (byte) (paraLevel & 1);

		if (isDefaultLevel) {
			paras_level[0] = defaultParaLevel;
			lastStrong = defaultParaLevel;
			state = SEEKING_STRONG_FOR_PARA;
		} else {
			paras_level[0] = paraLevel;
			state = NOT_SEEKING_STRONG;
		}
		/* count paragraphs and determine the paragraph level (P2..P3) */
		/*
		 * see comment on constant fields: the LEVEL_DEFAULT_XXX values are designed so
		 * that their low-order bit alone yields the intended default
		 */

		for (i = 0; i < originalLength; /* i is incremented in the loop */) {
			i0 = i; /* index of first code unit */
			uchar = UTF16.charAt(text, 0, originalLength, i);
			i += UTF16.getCharCount(uchar);
			i1 = i - 1; /* index of last code unit, gets the directional property */

			dirProp = (byte) getCustomizedClass(uchar);
			flags |= DirPropFlag(dirProp);
			dirProps[i1] = dirProp;
			if (i1 > i0) { /* set previous code units' properties to BN */
				flags |= DirPropFlag(BN);
				do {
					dirProps[--i1] = BN;
				} while (i1 > i0);
			}
			if (removeBidiControls && IsBidiControlChar(uchar)) {
				controlCount++;
			}
			if (dirProp == L) {
				if (state == SEEKING_STRONG_FOR_PARA) {
					paras_level[paraCount - 1] = 0;
					state = NOT_SEEKING_STRONG;
				} else if (state == SEEKING_STRONG_FOR_FSI) {
					if (stackLast <= MAX_EXPLICIT_LEVEL) {
						/* no need for next statement, already set by default */
						/* dirProps[isolateStartStack[stackLast]] = LRI; */
						flags |= DirPropFlag(LRI);
					}
					state = LOOKING_FOR_PDI;
				}
				lastStrong = L;
				continue;
			}
			if (dirProp == R || dirProp == AL) {
				if (state == SEEKING_STRONG_FOR_PARA) {
					paras_level[paraCount - 1] = 1;
					state = NOT_SEEKING_STRONG;
				} else if (state == SEEKING_STRONG_FOR_FSI) {
					if (stackLast <= MAX_EXPLICIT_LEVEL) {
						dirProps[isolateStartStack[stackLast]] = RLI;
						flags |= DirPropFlag(RLI);
					}
					state = LOOKING_FOR_PDI;
				}
				lastStrong = R;
				if (dirProp == AL)
					lastArabicPos = i - 1;
				continue;
			}
			if (dirProp >= FSI && dirProp <= RLI) { /* FSI, LRI or RLI */
				stackLast++;
				if (stackLast <= MAX_EXPLICIT_LEVEL) {
					isolateStartStack[stackLast] = i - 1;
					previousStateStack[stackLast] = state;
				}
				if (dirProp == FSI) {
					dirProps[i - 1] = LRI; /* default if no strong char */
					state = SEEKING_STRONG_FOR_FSI;
				} else
					state = LOOKING_FOR_PDI;
				continue;
			}
			if (dirProp == PDI) {
				if (state == SEEKING_STRONG_FOR_FSI) {
					if (stackLast <= MAX_EXPLICIT_LEVEL) {
						/* no need for next statement, already set by default */
						/* dirProps[isolateStartStack[stackLast]] = LRI; */
						flags |= DirPropFlag(LRI);
					}
				}
				if (stackLast >= 0) {
					if (stackLast <= MAX_EXPLICIT_LEVEL)
						state = previousStateStack[stackLast];
					stackLast--;
				}
				continue;
			}
			if (dirProp == B) {
				if (i < originalLength && uchar == CR && text[i] == LF) /* do nothing on the CR */
					continue;
				paras_limit[paraCount - 1] = i;
				if (isDefaultLevelInverse && lastStrong == R)
					paras_level[paraCount - 1] = 1;
				if ((reorderingOptions & OPTION_STREAMING) != 0) {
					/*
					 * When streaming, we only process whole paragraphs thus some updates are only
					 * done on paragraph boundaries
					 */
					length = i; /* i is index to next character */
					this.controlCount = controlCount;
				}
				if (i < originalLength) { /* B not last char in text */
					paraCount++;
					checkParaCount(); /* check that there is enough memory for a new para entry */
					if (isDefaultLevel) {
						paras_level[paraCount - 1] = defaultParaLevel;
						state = SEEKING_STRONG_FOR_PARA;
						lastStrong = defaultParaLevel;
					} else {
						paras_level[paraCount - 1] = paraLevel;
						state = NOT_SEEKING_STRONG;
					}
					stackLast = -1;
				}
				continue;
			}
		}
		/* +Ignore still open isolate sequences with overflow */
		if (stackLast > MAX_EXPLICIT_LEVEL) {
			stackLast = MAX_EXPLICIT_LEVEL;
			state = SEEKING_STRONG_FOR_FSI; /* to be on the safe side */
		}
		/* Resolve direction of still unresolved open FSI sequences */
		while (stackLast >= 0) {
			if (state == SEEKING_STRONG_FOR_FSI) {
				/* no need for next statement, already set by default */
				/* dirProps[isolateStartStack[stackLast]] = LRI; */
				flags |= DirPropFlag(LRI);
				break;
			}
			state = previousStateStack[stackLast];
			stackLast--;
		}
		/* When streaming, ignore text after the last paragraph separator */
		if ((reorderingOptions & OPTION_STREAMING) != 0) {
			if (length < originalLength)
				paraCount--;
		} else {
			paras_limit[paraCount - 1] = originalLength;
			this.controlCount = controlCount;
		}
		/*
		 * For inverse bidi, default para direction is RTL if there is a strong R or AL
		 * at either end of the paragraph
		 */
		if (isDefaultLevelInverse && lastStrong == R) {
			paras_level[paraCount - 1] = 1;
		}
		if (isDefaultLevel) {
			paraLevel = paras_level[0];
		}
		/*
		 * The following is needed to resolve the text direction for default level
		 * paragraphs containing no strong character
		 */
		for (i = 0; i < paraCount; i++)
			flags |= DirPropFlagLR(paras_level[i]);

		if (orderParagraphsLTR && (flags & DirPropFlag(B)) != 0) {
			flags |= DirPropFlag(L);
		}
	}

	/* helper methods for each allocated array */
	private void getDirPropsMemory(boolean mayAllocate, int len) {
		Object array = getMemory("DirProps", dirPropsMemory, Byte.TYPE, mayAllocate, len);
		dirPropsMemory = (byte[]) array;
	}

	void getDirPropsMemory(int len) {
		getDirPropsMemory(mayAllocateText, len);
	}

	/*------------------------------------------------------------------------*/

	/* additional methods used by constructor - always allow allocation */
	private void getInitialDirPropsMemory(int len) {
		getDirPropsMemory(true, len);
	}

	private void getInitialLevelsMemory(int len) {
		getLevelsMemory(true, len);
	}

	private void getInitialRunsMemory(int len) {
		getRunsMemory(true, len);
	}

	/* perform rules (Wn), (Nn), and (In) on a run of the text ------------------ */

	/*
	 * This implementation of the (Wn) rules applies all rules in one pass. In order
	 * to do so, it needs a look-ahead of typically 1 character (except for W5:
	 * sequences of ET) and keeps track of changes in a rule Wp that affect a later
	 * Wq (p<q).
	 *
	 * The (Nn) and (In) rules are also performed in that same single loop, but
	 * effectively one iteration behind for white space.
	 *
	 * Since all implicit rules are performed in one step, it is not necessary to
	 * actually store the intermediate directional properties in dirProps[].
	 */

	/**
	 * Get the length of the text.
	 *
	 * @return The length of the text that the <code>Bidi</code> object was created
	 *         for.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 * @stable ICU 3.8
	 */
	public int getLength() {
		verifyValidParaOrLine();
		return originalLength;
	}

	/**
	 * Get the level for one character.
	 *
	 * @param charIndex the index of a character.
	 *
	 * @return The level for the character at <code>charIndex</code>.
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code> or
	 *                                  <code>setLine</code>
	 * @throws IllegalArgumentException if charIndex is not in the range
	 *                                  <code>0&lt;=charIndex&lt;getProcessedLength()</code>
	 *
	 * @see #getProcessedLength
	 * @stable ICU 3.8
	 */
	public byte getLevelAt(int charIndex) {
		// for backward compatibility
		if (charIndex < 0 || charIndex >= length) {
			return (byte) getBaseLevel();
		}

		verifyValidParaOrLine();
		verifyRange(charIndex, 0, length);
		return BidiLine.getLevelAt(this, charIndex);
	}

	/* perform (L1) and (X9) ---------------------------------------------------- */

	/**
	 * Get an array of levels for each character.
	 * <p>
	 *
	 * Note that this method may allocate memory under some circumstances, unlike
	 * <code>getLevelAt()</code>.
	 *
	 * @return The levels array for the text, or <code>null</code> if an error
	 *         occurs.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 * @stable ICU 3.8
	 */
	byte[] getLevels() {
		verifyValidParaOrLine();
		if (length <= 0) {
			return new byte[0];
		}
		return BidiLine.getLevels(this);
	}

	private void getLevelsMemory(boolean mayAllocate, int len) {
		Object array = getMemory("Levels", levelsMemory, Byte.TYPE, mayAllocate, len);
		levelsMemory = (byte[]) array;
	}

	void getLevelsMemory(int len) {
		getLevelsMemory(mayAllocateText, len);
	}

	/**
	 * Compute the logical to visual run mapping
	 */
	void getLogicalToVisualRunsMap() {
		if (isGoodLogicalToVisualRunsMap) {
			return;
		}
		int count = countRuns();
		if ((logicalToVisualRunsMap == null) || (logicalToVisualRunsMap.length < count)) {
			logicalToVisualRunsMap = new int[count];
		}
		int i;
		long[] keys = new long[count];
		for (i = 0; i < count; i++) {
			keys[i] = ((long) (runs[i].start) << 32) + i;
		}
		Arrays.sort(keys);
		for (i = 0; i < count; i++) {
			logicalToVisualRunsMap[i] = (int) (keys[i] & 0x00000000FFFFFFFF);
		}
		isGoodLogicalToVisualRunsMap = true;
	}

	/*
	 * We are allowed to allocate memory if object==null or mayAllocate==true for
	 * each array that we need.
	 *
	 * Assume sizeNeeded>0. If object != null, then assume size > 0.
	 */
	private Object getMemory(String label, Object array, Class<?> arrayClass, boolean mayAllocate, int sizeNeeded) {
		int len = Array.getLength(array);

		/* we have at least enough memory and must not allocate */
		if (sizeNeeded == len) {
			return array;
		}
		if (!mayAllocate) {
			/* we must not allocate */
			if (sizeNeeded <= len) {
				return array;
			}
			throw new OutOfMemoryError("Failed to allocate memory for " + label);
		}
		/* we may try to grow or shrink */
		/*
		 * FOOD FOR THOUGHT: when shrinking it should be possible to avoid the
		 * allocation altogether and rely on this.length
		 */
		try {
			return Array.newInstance(arrayClass, sizeNeeded);
		} catch (Exception e) {
			throw new OutOfMemoryError("Failed to allocate memory for " + label);
		}
	}

	/**
	 * Get the paragraph level of the text.
	 *
	 * @return The paragraph level. If there are multiple paragraphs, their level
	 *         may vary if the required paraLevel is LEVEL_DEFAULT_LTR or
	 *         LEVEL_DEFAULT_RTL. In that case, the level of the first paragraph is
	 *         returned.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @see #LEVEL_DEFAULT_LTR
	 * @see #LEVEL_DEFAULT_RTL
	 * @see #getParagraph
	 * @see #getParagraphByIndex
	 * @stable ICU 3.8
	 */
	public byte getParaLevel() {
		verifyValidParaOrLine();
		return paraLevel;
	}

	/* determine the paragraph level at position index */
	byte GetParaLevelAt(int pindex) {
		if (defaultParaLevel == 0 || pindex < paras_limit[0])
			return paraLevel;
		int i;
		for (i = 1; i < paraCount; i++)
			if (pindex < paras_limit[i])
				break;
		if (i >= paraCount)
			i = paraCount - 1;
		return paras_level[i];
	}

	/**
	 * Return the level of the nth logical run in this line.
	 *
	 * @param run the index of the run, between 0 and <code>countRuns()-1</code>
	 *
	 * @return the level of the run
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code> or
	 *                                  <code>setLine</code>
	 * @throws IllegalArgumentException if <code>run</code> is not in the range
	 *                                  <code>0&lt;=run&lt;countRuns()</code>
	 * @stable ICU 3.8
	 */
	public int getRunLevel(int run) {
		verifyValidParaOrLine();
		BidiLine.getRuns(this);

		// for backward compatibility
		if (run < 0 || run >= runCount) {
			return getParaLevel();
		}

		getLogicalToVisualRunsMap();
		return runs[logicalToVisualRunsMap[run]].level;
	}

	/**
	 * Return the index of the character past the end of the nth logical run in this
	 * line, as an offset from the start of the line. For example, this will return
	 * the length of the line for the last run on the line.
	 *
	 * @param run the index of the run, between 0 and <code>countRuns()</code>
	 *
	 * @return the limit of the run
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code> or
	 *                                  <code>setLine</code>
	 * @throws IllegalArgumentException if <code>run</code> is not in the range
	 *                                  <code>0&lt;=run&lt;countRuns()</code>
	 * @stable ICU 3.8
	 */
	public int getRunLimit(int run) {
		verifyValidParaOrLine();
		BidiLine.getRuns(this);

		// for backward compatibility
		if (runCount == 1) {
			return length;
		}

		getLogicalToVisualRunsMap();
		int idx = logicalToVisualRunsMap[run];
		int len = idx == 0 ? runs[idx].limit : runs[idx].limit - runs[idx - 1].limit;
		return runs[idx].start + len;
	}

	private void getRunsMemory(boolean mayAllocate, int len) {
		Object array = getMemory("Runs", runsMemory, BidiRun.class, mayAllocate, len);
		runsMemory = (BidiRun[]) array;
	}

	void getRunsMemory(int len) {
		getRunsMemory(mayAllocateRuns, len);
	}

	/* paragraphs API methods ------------------------------------------------- */

	/**
	 * Return the index of the character at the start of the nth logical run in this
	 * line, as an offset from the start of the line.
	 *
	 * @param run the index of the run, between 0 and <code>countRuns()</code>
	 *
	 * @return the start of the run
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code> or
	 *                                  <code>setLine</code>
	 * @throws IllegalArgumentException if <code>run</code> is not in the range
	 *                                  <code>0&lt;=run&lt;countRuns()</code>
	 * @stable ICU 3.8
	 */
	public int getRunStart(int run) {
		verifyValidParaOrLine();
		BidiLine.getRuns(this);

		// for backward compatibility
		if (runCount == 1) {
			return 0;
		} else if (run == runCount) {
			return length;
		}

		getLogicalToVisualRunsMap();
		return runs[logicalToVisualRunsMap[run]].start;
	}

	/**
	 * Get a visual-to-logical index map (array) for the characters in the
	 * <code>Bidi</code> (paragraph or line) object.
	 * <p>
	 * Some values in the map may be <code>MAP_NOWHERE</code> if the corresponding
	 * text characters are Bidi marks inserted in the visual output by the option
	 * <code>OPTION_INSERT_MARKS</code>.
	 * <p>
	 * When the visual output is altered by using options of
	 * <code>writeReordered()</code> such as <code>INSERT_LRM_FOR_NUMERIC</code>,
	 * <code>KEEP_BASE_COMBINING</code>, <code>OUTPUT_REVERSE</code>,
	 * <code>REMOVE_BIDI_CONTROLS</code>, the logical positions returned may not be
	 * correct. It is advised to use, when possible, reordering options such as
	 * {@link #OPTION_INSERT_MARKS} and {@link #OPTION_REMOVE_CONTROLS}.
	 *
	 * @return an array of <code>getResultLength()</code> indexes which will reflect
	 *         the reordering of the characters.<br>
	 *         <br>
	 *         The index map will result in
	 *         <code>indexMap[visualIndex]==logicalIndex</code>, where
	 *         <code>indexMap</code> represents the returned array.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @see #getLogicalMap
	 * @see #getLogicalIndex
	 * @see #getResultLength
	 * @see #MAP_NOWHERE
	 * @see #OPTION_INSERT_MARKS
	 * @see #writeReordered
	 * @stable ICU 3.8
	 */
	private int[] getVisualMap() {
		/* countRuns() checks successful call to setPara/setLine */
		countRuns();
		if (resultLength <= 0) {
			return new int[0];
		}
		return BidiLine.getVisualMap(this);
	}

	/**
	 *
	 * Get a <code>BidiRun</code> object according to its index. BidiRun methods may
	 * be used to retrieve the run's logical start, length and level, which can be
	 * even for an LTR run or odd for an RTL run. In an RTL run, the character at
	 * the logical start is visually on the right of the displayed run. The length
	 * is the number of characters in the run.
	 * <p>
	 * <code>countRuns()</code> is normally called before the runs are retrieved.
	 *
	 * <p>
	 * Example:
	 *
	 * <pre>
	 * Bidi bidi = new Bidi();
	 * String text = "abc 123 DEFG xyz";
	 * bidi.setPara(text, Bidi.RTL, null);
	 * int i, count = bidi.countRuns(), logicalStart, visualIndex = 0, length;
	 * BidiRun run;
	 * for (i = 0; i &lt; count; ++i) {
	 * 	run = bidi.getVisualRun(i);
	 * 	logicalStart = run.getStart();
	 * 	length = run.getLength();
	 * 	if (Bidi.LTR == run.getEmbeddingLevel()) {
	 * 		do { // LTR
	 * 			show_char(text.charAt(logicalStart++), visualIndex++);
	 * 		} while (--length &gt; 0);
	 * 	} else {
	 * 		logicalStart += length; // logicalLimit
	 * 		do { // RTL
	 * 			show_char(text.charAt(--logicalStart), visualIndex++);
	 * 		} while (--length &gt; 0);
	 * 	}
	 * }
	 * </pre>
	 * <p>
	 * Note that in right-to-left runs, code like this places second surrogates
	 * before first ones (which is generally a bad idea) and combining characters
	 * before base characters.
	 * <p>
	 * Use of <code>{@link #writeReordered}</code>, optionally with the
	 * <code>{@link #KEEP_BASE_COMBINING}</code> option, can be considered in order
	 * to avoid these issues.
	 *
	 * @param runIndex is the number of the run in visual order, in the range
	 *                 <code>[0..countRuns()-1]</code>.
	 *
	 * @return a BidiRun object containing the details of the run. The
	 *         directionality of the run is <code>LTR==0</code> or
	 *         <code>RTL==1</code>, never <code>MIXED</code>.
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code> or
	 *                                  <code>setLine</code>
	 * @throws IllegalArgumentException if <code>runIndex</code> is not in the range
	 *                                  <code>0&lt;=runIndex&lt;countRuns()</code>
	 *
	 * @see #countRuns()
	 * @see com.ibm.icu.text.BidiRun
	 * @see com.ibm.icu.text.BidiRun#getStart()
	 * @see com.ibm.icu.text.BidiRun#getLength()
	 * @see com.ibm.icu.text.BidiRun#getEmbeddingLevel()
	 * @stable ICU 3.8
	 */
	BidiRun getVisualRun(int runIndex) {
		verifyValidParaOrLine();
		BidiLine.getRuns(this);
		verifyRange(runIndex, 0, runCount);
		return BidiLine.getVisualRun(this, runIndex);
	}

	/**
	 * Is this <code>Bidi</code> object set to perform the inverse Bidi algorithm?
	 * <p>
	 * Note: calling this method after setting the reordering mode with
	 * <code>setReorderingMode</code> will return <code>true</code> if the
	 * reordering mode was set to <code>REORDER_INVERSE_NUMBERS_AS_L</code>,
	 * <code>false</code> for all other values.
	 * </p>
	 *
	 * @return <code>true</code> if the <code>Bidi</code> object is set to perform
	 *         the inverse Bidi algorithm by handling numbers as L.
	 *
	 * @see #setInverse
	 * @see #setReorderingMode
	 * @see #REORDER_INVERSE_NUMBERS_AS_L
	 * @stable ICU 3.8
	 */
	public boolean isInverse() {
		return isInverse;
	}

	/**
	 * Return true if the line is all left-to-right text and the base direction is
	 * left-to-right.
	 *
	 * @return true if the line is all left-to-right text and the base direction is
	 *         left-to-right.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code>
	 * @stable ICU 3.8
	 */
	public boolean isLeftToRight() {
		return (getDirection() == LTR && (paraLevel & 1) == 0);
	}

	/**
	 * Return true if the line is not left-to-right or right-to-left. This means it
	 * either has mixed runs of left-to-right and right-to-left text, or the base
	 * direction differs from the direction of the only run of text.
	 *
	 * @return true if the line is not left-to-right or right-to-left.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code>
	 * @stable ICU 3.8
	 */
	public boolean isMixed() {
		return (!isLeftToRight() && !isRightToLeft());
	}

	/**
	 * Return true if the line is all right-to-left text, and the base direction is
	 * right-to-left
	 *
	 * @return true if the line is all right-to-left text, and the base direction is
	 *         right-to-left
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code>
	 * @stable ICU 3.8
	 */
	public boolean isRightToLeft() {
		return (getDirection() == RTL && (paraLevel & 1) == 1);
	}

	/**
	 * Specify whether block separators must be allocated level zero, so that
	 * successive paragraphs will progress from left to right. This method must be
	 * called before <code>setPara()</code>. Paragraph separators (B) may appear in
	 * the text. Setting them to level zero means that all paragraph separators
	 * (including one possibly appearing in the last text position) are kept in the
	 * reordered text after the text that they follow in the source text. When this
	 * feature is not enabled, a paragraph separator at the last position of the
	 * text before reordering will go to the first position of the reordered text
	 * when the paragraph level is odd.
	 *
	 * @param ordarParaLTR specifies whether paragraph separators (B) must receive
	 *                     level 0, so that successive paragraphs progress from left
	 *                     to right.
	 *
	 * @see #setPara
	 * @stable ICU 3.8
	 */
	public void orderParagraphsLTR(boolean ordarParaLTR) {
		orderParagraphsLTR = ordarParaLTR;
	}

	private void processPropertySeq(LevState levState, short _prop, int start, int limit) {
		byte cell;
		byte[][] impTab = levState.impTab;
		short[] impAct = levState.impAct;
		short oldStateSeq, actionSeq;
		byte level, addLevel;
		int start0, k;

		start0 = start; /* save original start position */
		oldStateSeq = levState.state;
		cell = impTab[oldStateSeq][_prop];
		levState.state = GetState(cell); /* isolate the new state */
		actionSeq = impAct[GetAction(cell)]; /* isolate the action */
		addLevel = impTab[levState.state][IMPTABLEVELS_RES];

		if (actionSeq != 0) {
			switch (actionSeq) {
			case 1: /* init ON seq */
				levState.startON = start0;
				break;

			case 2: /* prepend ON seq to current seq */
				start = levState.startON;
				break;

			case 3: /* EN/AN after R+ON */
				level = (byte) (levState.runLevel + 1);
				setLevelsOutsideIsolates(levState.startON, start0, level);
				break;

			case 4: /* EN/AN before R for NUMBERS_SPECIAL */
				level = (byte) (levState.runLevel + 2);
				setLevelsOutsideIsolates(levState.startON, start0, level);
				break;

			case 5: /* L or S after possible relevant EN/AN */
				/* check if we had EN after R/AL */
				if (levState.startL2EN >= 0) {
					addPoint(levState.startL2EN, LRM_BEFORE);
				}
				levState.startL2EN = -1; /* not within previous if since could also be -2 */
				/* check if we had any relevant EN/AN after R/AL */
				if ((insertPoints.points.length == 0) || (insertPoints.size <= insertPoints.confirmed)) {
					/* nothing, just clean up */
					levState.lastStrongRTL = -1;
					/* check if we have a pending conditional segment */
					level = impTab[oldStateSeq][IMPTABLEVELS_RES];
					if ((level & 1) != 0 && levState.startON > 0) { /* after ON */
						start = levState.startON; /* reset to basic run level */
					}
					if (_prop == _S) { /* add LRM before S */
						addPoint(start0, LRM_BEFORE);
						insertPoints.confirmed = insertPoints.size;
					}
					break;
				}
				/* reset previous RTL cont to level for LTR text */
				for (k = levState.lastStrongRTL + 1; k < start0; k++) {
					/* reset odd level, leave runLevel+2 as is */
					levels[k] = (byte) ((levels[k] - 2) & ~1);
				}
				/* mark insert points as confirmed */
				insertPoints.confirmed = insertPoints.size;
				levState.lastStrongRTL = -1;
				if (_prop == _S) { /* add LRM before S */
					addPoint(start0, LRM_BEFORE);
					insertPoints.confirmed = insertPoints.size;
				}
				break;

			case 6: /* R/AL after possible relevant EN/AN */
				/* just clean up */
				if (insertPoints.points.length > 0)
					/* remove all non confirmed insert points */
					insertPoints.size = insertPoints.confirmed;
				levState.startON = -1;
				levState.startL2EN = -1;
				levState.lastStrongRTL = limit - 1;
				break;

			case 7: /* EN/AN after R/AL + possible cont */
				/* check for real AN */

				if ((_prop == _AN) && (dirProps[start0] == AN)
						&& (reorderingMode != REORDER_INVERSE_FOR_NUMBERS_SPECIAL)) {
					/* real AN */
					if (levState.startL2EN == -1) { /* if no relevant EN already found */
						/* just note the rightmost digit as a strong RTL */
						levState.lastStrongRTL = limit - 1;
						break;
					}
					if (levState.startL2EN >= 0) { /* after EN, no AN */
						addPoint(levState.startL2EN, LRM_BEFORE);
						levState.startL2EN = -2;
					}
					/* note AN */
					addPoint(start0, LRM_BEFORE);
					break;
				}
				/* if first EN/AN after R/AL */
				if (levState.startL2EN == -1) {
					levState.startL2EN = start0;
				}
				break;

			case 8: /* note location of latest R/AL */
				levState.lastStrongRTL = limit - 1;
				levState.startON = -1;
				break;

			case 9: /* L after R+ON/EN/AN */
				/* include possible adjacent number on the left */
				for (k = start0 - 1; k >= 0 && ((levels[k] & 1) == 0); k--) {
				}
				if (k >= 0) {
					addPoint(k, RLM_BEFORE); /* add RLM before */
					insertPoints.confirmed = insertPoints.size; /* confirm it */
				}
				levState.startON = start0;
				break;

			case 10: /* AN after L */
				/* AN numbers between L text on both sides may be trouble. */
				/* tentatively bracket with LRMs; will be confirmed if followed by L */
				addPoint(start0, LRM_BEFORE); /* add LRM before */
				addPoint(start0, LRM_AFTER); /* add LRM after */
				break;

			case 11: /* R after L+ON/EN/AN */
				/* false alert, infirm LRMs around previous AN */
				insertPoints.size = insertPoints.confirmed;
				if (_prop == _S) { /* add RLM before S */
					addPoint(start0, RLM_BEFORE);
					insertPoints.confirmed = insertPoints.size;
				}
				break;

			case 12: /* L after L+ON/AN */
				level = (byte) (levState.runLevel + addLevel);
				for (k = levState.startON; k < start0; k++) {
					if (levels[k] < level) {
						levels[k] = level;
					}
				}
				insertPoints.confirmed = insertPoints.size; /* confirm inserts */
				levState.startON = start0;
				break;

			case 13: /* L after L+ON+EN/AN/ON */
				level = levState.runLevel;
				for (k = start0 - 1; k >= levState.startON; k--) {
					if (levels[k] == level + 3) {
						while (levels[k] == level + 3) {
							levels[k--] -= 2;
						}
						while (levels[k] == level) {
							k--;
						}
					}
					if (levels[k] == level + 2) {
						levels[k] = level;
						continue;
					}
					levels[k] = (byte) (level + 1);
				}
				break;

			case 14: /* R after L+ON+EN/AN/ON */
				level = (byte) (levState.runLevel + 1);
				for (k = start0 - 1; k >= levState.startON; k--) {
					if (levels[k] > level) {
						levels[k] -= 2;
					}
				}
				break;

			default: /* we should never get here */
				throw new IllegalStateException("Internal ICU error in processPropertySeq");
			}
		}
		if ((addLevel) != 0 || (start < start0)) {
			level = (byte) (levState.runLevel + addLevel);
			if (start >= levState.runStart) {
				for (k = start; k < limit; k++) {
					levels[k] = level;
				}
			} else {
				setLevelsOutsideIsolates(start, limit, level);
			}
		}
	}

	/*
	 * Resolve the explicit levels as specified by explicit embedding codes.
	 * Recalculate the flags to have them reflect the real properties after taking
	 * the explicit embeddings into account.
	 *
	 * The BiDi algorithm is designed to result in the same behavior whether
	 * embedding levels are externally specified (from "styled text", supposedly the
	 * preferred method) or set by explicit embedding codes (LRx, RLx, PDF, FSI,
	 * PDI) in the plain text. That is why (X9) instructs to remove all not-isolate
	 * explicit codes (and BN). However, in a real implementation, the removal of
	 * these codes and their index positions in the plain text is undesirable since
	 * it would result in reallocated, reindexed text. Instead, this implementation
	 * leaves the codes in there and just ignores them in the subsequent processing.
	 * In order to get the same reordering behavior, positions with a BN or a
	 * not-isolate explicit embedding code just get the same level assigned as the
	 * last "real" character.
	 *
	 * Some implementations, not this one, then overwrite some of these
	 * directionality properties at "real" same-level-run boundaries by L or R codes
	 * so that the resolution of weak types can be performed on the entire paragraph
	 * at once instead of having to parse it once more and perform that resolution
	 * on same-level-runs. This limits the scope of the implicit rules in
	 * effectively the same way as the run limits.
	 *
	 * Instead, this implementation does not modify these codes, except for paired
	 * brackets whose properties (ON) may be replaced by L or R. On one hand, the
	 * paragraph has to be scanned for same-level-runs, but on the other hand, this
	 * saves another loop to reset these codes, or saves making and modifying a copy
	 * of dirProps[].
	 *
	 *
	 * Note that (Pn) and (Xn) changed significantly from version 4 of the BiDi
	 * algorithm.
	 *
	 *
	 * Handling the stack of explicit levels (Xn):
	 *
	 * With the BiDi stack of explicit levels, as pushed with each LRE, RLE, LRO,
	 * RLO, LRI, RLI and FSI and popped with each PDF and PDI, the explicit level
	 * must never exceed MAX_EXPLICIT_LEVEL.
	 *
	 * In order to have a correct push-pop semantics even in the case of overflows,
	 * overflow counters and a valid isolate counter are used as described in UAX#9
	 * section 3.3.2 "Explicit Levels and Directions".
	 *
	 * This implementation assumes that MAX_EXPLICIT_LEVEL is odd.
	 *
	 * Returns the direction
	 *
	 */
	private byte resolveExplicitLevels() {
		int i = 0;
		byte dirProp;
		byte level = GetParaLevelAt(0);
		byte dirct;
		isolateCount = 0;

		/* determine if the text is mixed-directional or single-directional */
		dirct = directionFromFlags();

		/* we may not need to resolve any explicit levels */
		if (dirct != MIXED) {
			/* not mixed directionality: levels don't matter - trailingWSStart will be 0 */
			return dirct;
		}

		if (reorderingMode > REORDER_LAST_LOGICAL_TO_VISUAL) {
			/* inverse BiDi: mixed, but all characters are at the same embedding level */
			/* set all levels to the paragraph level */
			int paraIndex, start, limit;
			for (paraIndex = 0; paraIndex < paraCount; paraIndex++) {
				if (paraIndex == 0)
					start = 0;
				else
					start = paras_limit[paraIndex - 1];
				limit = paras_limit[paraIndex];
				level = paras_level[paraIndex];
				for (i = start; i < limit; i++)
					levels[i] = level;
			}
			return dirct; /* no bracket matching for inverse BiDi */
		}
		if ((flags & (MASK_EXPLICIT | MASK_ISO)) == 0) {
			/* no embeddings, set all levels to the paragraph level */
			/* we still have to perform bracket matching */
			int paraIndex, start, limit;
			BracketData bracketData = new BracketData();
			bracketInit(bracketData);
			for (paraIndex = 0; paraIndex < paraCount; paraIndex++) {
				if (paraIndex == 0)
					start = 0;
				else
					start = paras_limit[paraIndex - 1];
				limit = paras_limit[paraIndex];
				level = paras_level[paraIndex];
				for (i = start; i < limit; i++) {
					levels[i] = level;
					dirProp = dirProps[i];
					if (dirProp == BN)
						continue;
					if (dirProp == B) {
						if ((i + 1) < length) {
							if (text[i] == CR && text[i + 1] == LF)
								continue; /* skip CR when followed by LF */
							bracketProcessB(bracketData, level);
						}
						continue;
					}
					bracketProcessChar(bracketData, i);
				}
			}
			return dirct;
		}
		/* continue to perform (Xn) */

		/*
		 * (X1) level is set for all codes, embeddingLevel keeps track of the push/pop
		 * operations
		 */
		/*
		 * both variables may carry the LEVEL_OVERRIDE flag to indicate the override
		 * status
		 */
		byte embeddingLevel = level, newLevel;
		byte previousLevel = level; /* previous level for regular (not CC) characters */
		int lastCcPos = 0; /* index of last effective LRx,RLx, PDx */

		/*
		 * The following stack remembers the embedding level and the ISOLATE flag of
		 * level runs. stackLast points to its current entry.
		 */
		short[] stack = new short[MAX_EXPLICIT_LEVEL + 2]; /*
															 * we never push anything >= MAX_EXPLICIT_LEVEL but we need
															 * one more entry as base
															 */
		int stackLast = 0;
		int overflowIsolateCount = 0;
		int overflowEmbeddingCount = 0;
		int validIsolateCount = 0;
		BracketData bracketData = new BracketData();
		bracketInit(bracketData);
		stack[0] = level; /* initialize base entry to para level, no override, no isolate */

		/* recalculate the flags */
		flags = 0;

		for (i = 0; i < length; i++) {
			dirProp = dirProps[i];
			switch (dirProp) {
			case LRE:
			case RLE:
			case LRO:
			case RLO:
				/* (X2, X3, X4, X5) */
				flags |= DirPropFlag(BN);
				levels[i] = previousLevel;
				if (dirProp == LRE || dirProp == LRO) {
					/* least greater even level */
					newLevel = (byte) ((embeddingLevel + 2) & ~(LEVEL_OVERRIDE | 1));
				} else {
					/* least greater odd level */
					newLevel = (byte) ((NoOverride(embeddingLevel) + 1) | 1);
				}
				if (newLevel <= MAX_EXPLICIT_LEVEL && overflowIsolateCount == 0 && overflowEmbeddingCount == 0) {
					lastCcPos = i;
					embeddingLevel = newLevel;
					if (dirProp == LRO || dirProp == RLO)
						embeddingLevel |= LEVEL_OVERRIDE;
					stackLast++;
					stack[stackLast] = embeddingLevel;
					/*
					 * we don't need to set LEVEL_OVERRIDE off for LRE and RLE since this has
					 * already been done for newLevel which is the source for embeddingLevel.
					 */
				} else {
					if (overflowIsolateCount == 0)
						overflowEmbeddingCount++;
				}
				break;
			case PDF:
				/* (X7) */
				flags |= DirPropFlag(BN);
				levels[i] = previousLevel;
				/* handle all the overflow cases first */
				if (overflowIsolateCount > 0) {
					break;
				}
				if (overflowEmbeddingCount > 0) {
					overflowEmbeddingCount--;
					break;
				}
				if (stackLast > 0 && stack[stackLast] < ISOLATE) { /* not an isolate entry */
					lastCcPos = i;
					stackLast--;
					embeddingLevel = (byte) stack[stackLast];
				}
				break;
			case LRI:
			case RLI:
				flags |= DirPropFlag(ON) | DirPropFlagLR(embeddingLevel);
				levels[i] = NoOverride(embeddingLevel);
				if (NoOverride(embeddingLevel) != NoOverride(previousLevel)) {
					bracketProcessBoundary(bracketData, lastCcPos, previousLevel, embeddingLevel);
					flags |= DirPropFlagMultiRuns;
				}
				previousLevel = embeddingLevel;
				/* (X5a, X5b) */
				if (dirProp == LRI)
					/* least greater even level */
					newLevel = (byte) ((embeddingLevel + 2) & ~(LEVEL_OVERRIDE | 1));
				else
					/* least greater odd level */
					newLevel = (byte) ((NoOverride(embeddingLevel) + 1) | 1);
				if (newLevel <= MAX_EXPLICIT_LEVEL && overflowIsolateCount == 0 && overflowEmbeddingCount == 0) {
					flags |= DirPropFlag(dirProp);
					lastCcPos = i;
					validIsolateCount++;
					if (validIsolateCount > isolateCount)
						isolateCount = validIsolateCount;
					embeddingLevel = newLevel;
					/*
					 * we can increment stackLast without checking because newLevel will exceed
					 * UBIDI_MAX_EXPLICIT_LEVEL before stackLast overflows
					 */
					stackLast++;
					stack[stackLast] = (short) (embeddingLevel + ISOLATE);
					bracketProcessLRI_RLI(bracketData, embeddingLevel);
				} else {
					/* make it WS so that it is handled by adjustWSLevels() */
					dirProps[i] = WS;
					overflowIsolateCount++;
				}
				break;
			case PDI:
				if (NoOverride(embeddingLevel) != NoOverride(previousLevel)) {
					bracketProcessBoundary(bracketData, lastCcPos, previousLevel, embeddingLevel);
					flags |= DirPropFlagMultiRuns;
				}
				/* (X6a) */
				if (overflowIsolateCount > 0) {
					overflowIsolateCount--;
					/* make it WS so that it is handled by adjustWSLevels() */
					dirProps[i] = WS;
				} else if (validIsolateCount > 0) {
					flags |= DirPropFlag(PDI);
					lastCcPos = i;
					overflowEmbeddingCount = 0;
					while (stack[stackLast] < ISOLATE) /* pop embedding entries */
						stackLast--; /* until the last isolate entry */
					stackLast--; /* pop also the last isolate entry */
					validIsolateCount--;
					bracketProcessPDI(bracketData);
				} else
					/* make it WS so that it is handled by adjustWSLevels() */
					dirProps[i] = WS;
				embeddingLevel = (byte) (stack[stackLast] & ~ISOLATE);
				flags |= DirPropFlag(ON) | DirPropFlagLR(embeddingLevel);
				previousLevel = embeddingLevel;
				levels[i] = NoOverride(embeddingLevel);
				break;
			case B:
				flags |= DirPropFlag(B);
				levels[i] = GetParaLevelAt(i);
				if ((i + 1) < length) {
					if (text[i] == CR && text[i + 1] == LF)
						break; /* skip CR when followed by LF */
					overflowEmbeddingCount = overflowIsolateCount = 0;
					validIsolateCount = 0;
					stackLast = 0;
					previousLevel = embeddingLevel = GetParaLevelAt(i + 1);
					stack[0] = embeddingLevel; /* initialize base entry to para level, no override, no isolate */
					bracketProcessB(bracketData, embeddingLevel);
				}
				break;
			case BN:
				/* BN, LRE, RLE, and PDF are supposed to be removed (X9) */
				/* they will get their levels set correctly in adjustWSLevels() */
				levels[i] = previousLevel;
				flags |= DirPropFlag(BN);
				break;
			default:
				/* all other types are normal characters and get the "real" level */
				if (NoOverride(embeddingLevel) != NoOverride(previousLevel)) {
					bracketProcessBoundary(bracketData, lastCcPos, previousLevel, embeddingLevel);
					flags |= DirPropFlagMultiRuns;
					if ((embeddingLevel & LEVEL_OVERRIDE) != 0)
						flags |= DirPropFlagO(embeddingLevel);
					else
						flags |= DirPropFlagE(embeddingLevel);
				}
				previousLevel = embeddingLevel;
				levels[i] = embeddingLevel;
				bracketProcessChar(bracketData, i);
				/* the dirProp may have been changed in bracketProcessChar() */
				flags |= DirPropFlag(dirProps[i]);
				break;
			}
		}
		if ((flags & MASK_EMBEDDING) != 0) {
			flags |= DirPropFlagLR(paraLevel);
		}
		if (orderParagraphsLTR && (flags & DirPropFlag(B)) != 0) {
			flags |= DirPropFlag(L);
		}
		/* again, determine if the text is mixed-directional or single-directional */
		dirct = directionFromFlags();

		return dirct;
	}

	private void resolveImplicitLevels(int start, int limit, short sor, short eor) {
		byte dirProp;
		LevState levState = new LevState();
		int i, start1, start2;
		short oldStateImp, stateImp, actionImp;
		short gprop, resProp, cell;
		boolean inverseRTL;
		short nextStrongProp = R;
		int nextStrongPos = -1;

		/* check for RTL inverse Bidi mode */
		/*
		 * FOOD FOR THOUGHT: in case of RTL inverse Bidi, it would make sense to loop on
		 * the text characters from end to start. This would need a different properties
		 * state table (at least different actions) and different levels state tables
		 * (maybe very similar to the LTR corresponding ones.
		 */
		inverseRTL = ((start < lastArabicPos) && ((GetParaLevelAt(start) & 1) > 0)
				&& (reorderingMode == REORDER_INVERSE_LIKE_DIRECT
						|| reorderingMode == REORDER_INVERSE_FOR_NUMBERS_SPECIAL));
		/* initialize for property and levels state table */
		levState.startL2EN = -1; /* used for INVERSE_LIKE_DIRECT_WITH_MARKS */
		levState.lastStrongRTL = -1; /* used for INVERSE_LIKE_DIRECT_WITH_MARKS */
		levState.runStart = start;
		levState.runLevel = levels[start];
		levState.impTab = impTabPair.imptab[levState.runLevel & 1];
		levState.impAct = impTabPair.impact[levState.runLevel & 1];

		/*
		 * The isolates[] entries contain enough information to resume the bidi
		 * algorithm in the same state as it was when it was interrupted by an isolate
		 * sequence.
		 */
		if (dirProps[start] == PDI) {
			levState.startON = isolates[isolateCount].startON;
			start1 = isolates[isolateCount].start1;
			stateImp = isolates[isolateCount].stateImp;
			levState.state = isolates[isolateCount].state;
			isolateCount--;
		} else {
			levState.startON = -1;
			start1 = start;
			if (dirProps[start] == NSM)
				stateImp = (short) (1 + sor);
			else
				stateImp = 0;
			levState.state = 0;
			processPropertySeq(levState, sor, start, start);
		}
		start2 = start; /* to make the Java compiler happy */

		for (i = start; i <= limit; i++) {
			if (i >= limit) {
				int k;
				for (k = limit - 1; k > start && (DirPropFlag(dirProps[k]) & MASK_BN_EXPLICIT) != 0; k--)
					;
				dirProp = dirProps[k];
				if (dirProp == LRI || dirProp == RLI)
					break; /* no forced closing for sequence ending with LRI/RLI */
				gprop = eor;
			} else {
				byte prop, prop1;
				prop = dirProps[i];
				if (prop == B)
					isolateCount = -1; /* current isolates stack entry == none */
				if (inverseRTL) {
					if (prop == AL) {
						/* AL before EN does not make it AN */
						prop = R;
					} else if (prop == EN) {
						if (nextStrongPos <= i) {
							/* look for next strong char (L/R/AL) */
							int j;
							nextStrongProp = R; /* set default */
							nextStrongPos = limit;
							for (j = i + 1; j < limit; j++) {
								prop1 = dirProps[j];
								if (prop1 == L || prop1 == R || prop1 == AL) {
									nextStrongProp = prop1;
									nextStrongPos = j;
									break;
								}
							}
						}
						if (nextStrongProp == AL) {
							prop = AN;
						}
					}
				}
				gprop = groupProp[prop];
			}
			oldStateImp = stateImp;
			cell = impTabProps[oldStateImp][gprop];
			stateImp = GetStateProps(cell); /* isolate the new state */
			actionImp = GetActionProps(cell); /* isolate the action */
			if ((i == limit) && (actionImp == 0)) {
				/* there is an unprocessed sequence if its property == eor */
				actionImp = 1; /* process the last sequence */
			}
			if (actionImp != 0) {
				resProp = impTabProps[oldStateImp][IMPTABPROPS_RES];
				switch (actionImp) {
				case 1: /* process current seq1, init new seq1 */
					processPropertySeq(levState, resProp, start1, i);
					start1 = i;
					break;
				case 2: /* init new seq2 */
					start2 = i;
					break;
				case 3: /* process seq1, process seq2, init new seq1 */
					processPropertySeq(levState, resProp, start1, start2);
					processPropertySeq(levState, _ON, start2, i);
					start1 = i;
					break;
				case 4: /* process seq1, set seq1=seq2, init new seq2 */
					processPropertySeq(levState, resProp, start1, start2);
					start1 = start2;
					start2 = i;
					break;
				default: /* we should never get here */
					throw new IllegalStateException("Internal ICU error in resolveImplicitLevels");
				}
			}
		}

		/* look for the last char not a BN or LRE/RLE/LRO/RLO/PDF */
		for (i = limit - 1; i > start && (DirPropFlag(dirProps[i]) & MASK_BN_EXPLICIT) != 0; i--)
			;
		dirProp = dirProps[i];
		if ((dirProp == LRI || dirProp == RLI) && limit < length) {
			isolateCount++;
			if (isolates[isolateCount] == null)
				isolates[isolateCount] = new Isolate();
			isolates[isolateCount].stateImp = stateImp;
			isolates[isolateCount].state = levState.state;
			isolates[isolateCount].start1 = start1;
			isolates[isolateCount].startON = levState.startON;
		} else
			processPropertySeq(levState, eor, limit, limit);
	}

	private void setLevelsOutsideIsolates(int start, int limit, byte level) {
		byte dirProp;
		int isolateCount = 0, k;
		for (k = start; k < limit; k++) {
			dirProp = dirProps[k];
			if (dirProp == PDI)
				isolateCount--;
			if (isolateCount == 0) {
				levels[k] = level;
			}
			if (dirProp == LRI || dirProp == RLI)
				isolateCount++;
		}
	}

	/**
	 * <code>setLine()</code> returns a <code>Bidi</code> object to contain the
	 * reordering information, especially the resolved levels, for all the
	 * characters in a line of text. This line of text is specified by referring to
	 * a <code>Bidi</code> object representing this information for a piece of text
	 * containing one or more paragraphs, and by specifying a range of indexes in
	 * this text.
	 * <p>
	 * In the new line object, the indexes will range from 0 to
	 * <code>limit-start-1</code>.
	 * <p>
	 *
	 * This is used after calling <code>setPara()</code> for a piece of text, and
	 * after line-breaking on that text. It is not necessary if each paragraph is
	 * treated as a single line.
	 * <p>
	 *
	 * After line-breaking, rules (L1) and (L2) for the treatment of trailing WS and
	 * for reordering are performed on a <code>Bidi</code> object that represents a
	 * line.
	 * <p>
	 *
	 * <strong>Important: </strong>the line <code>Bidi</code> object may reference
	 * data within the global text <code>Bidi</code> object. You should not alter
	 * the content of the global text object until you are finished using the line
	 * object.
	 *
	 * @param start is the line's first index into the text.
	 *
	 * @param limit is just behind the line's last index into the text (its last
	 *              index +1).
	 *
	 * @return a <code>Bidi</code> object that will now represent a line of the
	 *         text.
	 *
	 * @throws IllegalStateException    if this call is not preceded by a successful
	 *                                  call to <code>setPara</code>
	 * @throws IllegalArgumentException if start and limit are not in the range
	 *                                  <code>0&lt;=start&lt;limit&lt;=getProcessedLength()</code>,
	 *                                  or if the specified line crosses a paragraph
	 *                                  boundary
	 *
	 * @see #setPara
	 * @see #getProcessedLength
	 * @stable ICU 3.8
	 */
	public Bidi setLine(Bidi bidi, BidiBase bidiBase, Bidi newBidi, BidiBase newBidiBase, int start, int limit) {
		verifyValidPara();
		verifyRange(start, 0, limit);
		verifyRange(limit, 0, length + 1);

		return BidiLine.setLine(this, newBidi, newBidiBase, start, limit);
	}

	/**
	 * Perform the Unicode Bidi algorithm on a given paragraph, as defined in the
	 * <a href="http://www.unicode.org/reports/tr9/">Unicode Standard Annex #9:
	 * Unicode Bidirectional Algorithm</a>, version 13, also described in The
	 * Unicode Standard, Version 4.0 .
	 * <p>
	 *
	 * This method takes a paragraph of text and computes the
	 * left-right-directionality of each character. The text should not contain any
	 * Unicode block separators.
	 * <p>
	 *
	 * The RUN_DIRECTION attribute in the text, if present, determines the base
	 * direction (left-to-right or right-to-left). If not present, the base
	 * direction is computed using the Unicode Bidirectional Algorithm, defaulting
	 * to left-to-right if there are no strong directional characters in the text.
	 * This attribute, if present, must be applied to all the text in the paragraph.
	 * <p>
	 *
	 * The BIDI_EMBEDDING attribute in the text, if present, represents embedding
	 * level information. Negative values from -1 to -62 indicate overrides at the
	 * absolute value of the level. Positive values from 1 to 62 indicate
	 * embeddings. Where values are zero or not defined, the base embedding level as
	 * determined by the base direction is assumed.
	 * <p>
	 *
	 * The NUMERIC_SHAPING attribute in the text, if present, converts European
	 * digits to other decimal digits before running the bidi algorithm. This
	 * attribute, if present, must be applied to all the text in the paragraph.
	 *
	 * If the entire text is all of the same directionality, then the method may not
	 * perform all the steps described by the algorithm, i.e., some levels may not
	 * be the same as if all steps were performed. This is not relevant for
	 * unidirectional text.<br>
	 * For example, in pure LTR text with numbers the numbers would get a resolved
	 * level of 2 higher than the surrounding text according to the algorithm. This
	 * implementation may set all resolved levels to the same value in such a case.
	 * <p>
	 *
	 * @param paragraph a paragraph of text with optional character and paragraph
	 *                  attribute information
	 * @stable ICU 3.8
	 */
	public void setPara(AttributedCharacterIterator paragraph) {
		byte paraLvl;
		char ch = paragraph.first();
		Boolean runDirection = (Boolean) paragraph.getAttribute(TextAttribute.RUN_DIRECTION);
		Object shaper = paragraph.getAttribute(TextAttribute.NUMERIC_SHAPING);

		if (runDirection == null) {
			paraLvl = LEVEL_DEFAULT_LTR;
		} else {
			paraLvl = (runDirection.equals(TextAttribute.RUN_DIRECTION_LTR)) ? LTR : RTL;
		}

		byte[] lvls = null;
		int len = paragraph.getEndIndex() - paragraph.getBeginIndex();
		byte[] embeddingLevels = new byte[len];
		char[] txt = new char[len];
		int i = 0;
		while (ch != AttributedCharacterIterator.DONE) {
			txt[i] = ch;
			Integer embedding = (Integer) paragraph.getAttribute(TextAttribute.BIDI_EMBEDDING);
			if (embedding != null) {
				byte level = embedding.byteValue();
				if (level == 0) {
					/* no-op */
				} else if (level < 0) {
					lvls = embeddingLevels;
					embeddingLevels[i] = (byte) ((0 - level) | LEVEL_OVERRIDE);
				} else {
					lvls = embeddingLevels;
					embeddingLevels[i] = level;
				}
			}
			ch = paragraph.next();
			++i;
		}

		if (shaper != null) {
			((NumericShaper) shaper).shape(txt, 0, len);
		}
		setPara(txt, paraLvl, lvls);
	}

	/**
	 * Perform the Unicode Bidi algorithm. It is defined in the
	 * <a href="http://www.unicode.org/reports/tr9/">Unicode Standard Annex #9:
	 * Unicode Bidirectional Algorithm</a>, version 13, also described in The
	 * Unicode Standard, Version 4.0 .
	 * <p>
	 *
	 * This method takes a piece of plain text containing one or more paragraphs,
	 * with or without externally specified embedding levels from <i>styled</i> text
	 * and computes the left-right-directionality of each character.
	 * <p>
	 *
	 * If the entire text is all of the same directionality, then the method may not
	 * perform all the steps described by the algorithm, i.e., some levels may not
	 * be the same as if all steps were performed. This is not relevant for
	 * unidirectional text.<br>
	 * For example, in pure LTR text with numbers the numbers would get a resolved
	 * level of 2 higher than the surrounding text according to the algorithm. This
	 * implementation may set all resolved levels to the same value in such a case.
	 *
	 * The text can be composed of multiple paragraphs. Occurrence of a block
	 * separator in the text terminates a paragraph, and whatever comes next starts
	 * a new paragraph. The exception to this rule is when a Carriage Return (CR) is
	 * followed by a Line Feed (LF). Both CR and LF are block separators, but in
	 * that case, the pair of characters is considered as terminating the preceding
	 * paragraph, and a new paragraph will be started by a character coming after
	 * the LF.
	 *
	 * The text is stored internally as an array of characters. Therefore the
	 * documentation will refer to indexes of the characters in the text.
	 *
	 * @param chars           contains the text that the Bidi algorithm will be
	 *                        performed on. This text can be retrieved with
	 *                        <code>getText()</code> or
	 *                        <code>getTextAsString</code>.<br>
	 *
	 * @param paraLevel       specifies the default level for the text; it is
	 *                        typically 0 (LTR) or 1 (RTL). If the method shall
	 *                        determine the paragraph level from the text, then
	 *                        <code>paraLevel</code> can be set to either
	 *                        <code>LEVEL_DEFAULT_LTR</code> or
	 *                        <code>LEVEL_DEFAULT_RTL</code>; if the text contains
	 *                        multiple paragraphs, the paragraph level shall be
	 *                        determined separately for each paragraph; if a
	 *                        paragraph does not include any strongly typed
	 *                        character, then the desired default is used (0 for LTR
	 *                        or 1 for RTL). Any other value between 0 and
	 *                        <code>MAX_EXPLICIT_LEVEL</code> is also valid, with
	 *                        odd levels indicating RTL.
	 *
	 * @param embeddingLevels (in) may be used to preset the embedding and override
	 *                        levels, ignoring characters like LRE and PDF in the
	 *                        text. A level overrides the directional property of
	 *                        its corresponding (same index) character if the level
	 *                        has the <code>LEVEL_OVERRIDE</code> bit set.<br>
	 *                        <br>
	 *                        Except for that bit, it must be
	 *                        <code>paraLevel<=embeddingLevels[]<=MAX_EXPLICIT_LEVEL</code>,
	 *                        with one exception: a level of zero may be specified
	 *                        for a paragraph separator even if
	 *                        <code>paraLevel&gt;0</code> when multiple paragraphs
	 *                        are submitted in the same call to
	 *                        <code>setPara()</code>.<br>
	 *                        <br>
	 *                        <strong>Caution: </strong>A reference to this array,
	 *                        not a copy of the levels, will be stored in the
	 *                        <code>Bidi</code> object; the
	 *                        <code>embeddingLevels</code> should not be modified to
	 *                        avoid unexpected results on subsequent Bidi
	 *                        operations. However, the <code>setPara()</code> and
	 *                        <code>setLine()</code> methods may modify some or all
	 *                        of the levels.<br>
	 *                        <br>
	 *                        <strong>Note:</strong> the
	 *                        <code>embeddingLevels</code> array must have one entry
	 *                        for each character in <code>text</code>.
	 *
	 * @throws IllegalArgumentException if the values in embeddingLevels are not
	 *                                  within the allowed range
	 *
	 * @see #LEVEL_DEFAULT_LTR
	 * @see #LEVEL_DEFAULT_RTL
	 * @see #LEVEL_OVERRIDE
	 * @see #MAX_EXPLICIT_LEVEL
	 * @stable ICU 3.8
	 */
	void setPara(char[] chars, byte paraLevel, byte[] embeddingLevels) {
		/* check the argument values */
		if (paraLevel < LEVEL_DEFAULT_LTR) {
			verifyRange(paraLevel, 0, MAX_EXPLICIT_LEVEL + 1);
		}
		if (chars == null) {
			chars = new char[0];
		}

		/* special treatment for RUNS_ONLY mode */
		if (reorderingMode == REORDER_RUNS_ONLY) {
			setParaRunsOnly(chars, paraLevel);
			return;
		}

		/* initialize the Bidi object */
		this.paraBidi = null; /* mark unfinished setPara */
		this.text = chars;
		this.length = this.originalLength = this.resultLength = text.length;
		this.paraLevel = paraLevel;
		this.direction = (byte) (paraLevel & 1);
		this.paraCount = 1;

		/*
		 * Allocate zero-length arrays instead of setting to null here; then checks for
		 * null in various places can be eliminated.
		 */
		dirProps = new byte[0];
		levels = new byte[0];
		runs = new BidiRun[0];
		isGoodLogicalToVisualRunsMap = false;
		insertPoints.size = 0; /* clean up from last call */
		insertPoints.confirmed = 0; /* clean up from last call */

		/*
		 * Save the original paraLevel if contextual; otherwise, set to 0.
		 */
		defaultParaLevel = IsDefaultLevel(paraLevel) ? paraLevel : 0;

		if (length == 0) {
			/*
			 * For an empty paragraph, create a Bidi object with the paraLevel and the flags
			 * and the direction set but without allocating zero-length arrays. There is
			 * nothing more to do.
			 */
			if (IsDefaultLevel(paraLevel)) {
				this.paraLevel &= 1;
				defaultParaLevel = 0;
			}
			flags = DirPropFlagLR(paraLevel);
			runCount = 0;
			paraCount = 0;
			setParaSuccess();
			return;
		}

		runCount = -1;

		/*
		 * Get the directional properties, the flags bit-set, and determine the
		 * paragraph level if necessary.
		 */
		getDirPropsMemory(length);
		dirProps = dirPropsMemory;
		getDirProps();
		/* the processed length may have changed if OPTION_STREAMING is set */
		trailingWSStart = length; /* the levels[] will reflect the WS run */

		/* are explicit levels specified? */
		if (embeddingLevels == null) {
			/* no: determine explicit levels according to the (Xn) rules */
			getLevelsMemory(length);
			levels = levelsMemory;
			direction = resolveExplicitLevels();
		} else {
			/*
			 * set BN for all explicit codes, check that all levels are 0 or
			 * paraLevel..MAX_EXPLICIT_LEVEL
			 */
			levels = embeddingLevels;
			direction = checkExplicitLevels();
		}

		/* allocate isolate memory */
		if (isolateCount > 0) {
			if (isolates == null || isolates.length < isolateCount)
				isolates = new Isolate[isolateCount + 3]; /* keep some reserve */
		}
		isolateCount = -1; /* current isolates stack entry == none */

		/*
		 * The steps after (X9) in the Bidi algorithm are performed only if the
		 * paragraph text has mixed directionality!
		 */
		switch (direction) {
		case LTR:
			/* all levels are implicitly at paraLevel (important for getLevels()) */
			trailingWSStart = 0;
			break;
		case RTL:
			/* all levels are implicitly at paraLevel (important for getLevels()) */
			trailingWSStart = 0;
			break;
		default:
			/*
			 * Choose the right implicit state table
			 */
			switch (reorderingMode) {
			case REORDER_DEFAULT:
				this.impTabPair = impTab_DEFAULT;
				break;
			case REORDER_NUMBERS_SPECIAL:
				this.impTabPair = impTab_NUMBERS_SPECIAL;
				break;
			case REORDER_GROUP_NUMBERS_WITH_R:
				this.impTabPair = impTab_GROUP_NUMBERS_WITH_R;
				break;
			case REORDER_RUNS_ONLY:
				/* we should never get here */
				throw new InternalError("Internal ICU error in setPara");
			/* break; */
			case REORDER_INVERSE_NUMBERS_AS_L:
				this.impTabPair = impTab_INVERSE_NUMBERS_AS_L;
				break;
			case REORDER_INVERSE_LIKE_DIRECT:
				if ((reorderingOptions & OPTION_INSERT_MARKS) != 0) {
					this.impTabPair = impTab_INVERSE_LIKE_DIRECT_WITH_MARKS;
				} else {
					this.impTabPair = impTab_INVERSE_LIKE_DIRECT;
				}
				break;
			case REORDER_INVERSE_FOR_NUMBERS_SPECIAL:
				if ((reorderingOptions & OPTION_INSERT_MARKS) != 0) {
					this.impTabPair = impTab_INVERSE_FOR_NUMBERS_SPECIAL_WITH_MARKS;
				} else {
					this.impTabPair = impTab_INVERSE_FOR_NUMBERS_SPECIAL;
				}
				break;
			}
			/*
			 * If there are no external levels specified and there are no significant
			 * explicit level codes in the text, then we can treat the entire paragraph as
			 * one run. Otherwise, we need to perform the following rules on runs of the
			 * text with the same embedding levels. (X10) "Significant" explicit level codes
			 * are ones that actually affect non-BN characters. Examples for "insignificant"
			 * ones are empty embeddings LRE-PDF, LRE-RLE-PDF-PDF, etc.
			 */
			if (embeddingLevels == null && paraCount <= 1 && (flags & DirPropFlagMultiRuns) == 0) {
				resolveImplicitLevels(0, length, GetLRFromLevel(GetParaLevelAt(0)),
						GetLRFromLevel(GetParaLevelAt(length - 1)));
			} else {
				/* sor, eor: start and end types of same-level-run */
				int start, limit = 0;
				byte level, nextLevel;
				short sor, eor;

				/*
				 * determine the first sor and set eor to it because of the loop body (sor=eor
				 * there)
				 */
				level = GetParaLevelAt(0);
				nextLevel = levels[0];
				if (level < nextLevel) {
					eor = GetLRFromLevel(nextLevel);
				} else {
					eor = GetLRFromLevel(level);
				}

				do {
					/* determine start and limit of the run (end points just behind the run) */

					/* the values for this run's start are the same as for the previous run's end */
					start = limit;
					level = nextLevel;
					if ((start > 0) && (dirProps[start - 1] == B)) {
						/* except if this is a new paragraph, then set sor = para level */
						sor = GetLRFromLevel(GetParaLevelAt(start));
					} else {
						sor = eor;
					}

					/* search for the limit of this run */
					while ((++limit < length)
							&& ((levels[limit] == level) || ((DirPropFlag(dirProps[limit]) & MASK_BN_EXPLICIT) != 0))) {
					}

					/* get the correct level of the next run */
					if (limit < length) {
						nextLevel = levels[limit];
					} else {
						nextLevel = GetParaLevelAt(length - 1);
					}

					/* determine eor from max(level, nextLevel); sor is last run's eor */
					if (NoOverride(level) < NoOverride(nextLevel)) {
						eor = GetLRFromLevel(nextLevel);
					} else {
						eor = GetLRFromLevel(level);
					}

					/*
					 * if the run consists of overridden directional types, then there are no
					 * implicit types to be resolved
					 */
					if ((level & LEVEL_OVERRIDE) == 0) {
						resolveImplicitLevels(start, limit, sor, eor);
					} else {
						/* remove the LEVEL_OVERRIDE flags */
						do {
							levels[start++] &= ~LEVEL_OVERRIDE;
						} while (start < limit);
					}
				} while (limit < length);
			}

			/* reset the embedding levels for some non-graphic characters (L1), (X9) */
			adjustWSLevels();

			break;
		}

		/*
		 * add RLM for inverse Bidi with contextual orientation resolving to RTL which
		 * would not round-trip otherwise
		 */
		if ((defaultParaLevel > 0) && ((reorderingOptions & OPTION_INSERT_MARKS) != 0)
				&& ((reorderingMode == REORDER_INVERSE_LIKE_DIRECT)
						|| (reorderingMode == REORDER_INVERSE_FOR_NUMBERS_SPECIAL))) {
			int start, last;
			byte level;
			byte dirProp;
			for (int i = 0; i < paraCount; i++) {
				last = paras_limit[i] - 1;
				level = paras_level[i];
				if (level == 0)
					continue; /* LTR paragraph */
				start = i == 0 ? 0 : paras_limit[i - 1];
				for (int j = last; j >= start; j--) {
					dirProp = dirProps[j];
					if (dirProp == L) {
						if (j < last) {
							while (dirProps[last] == B) {
								last--;
							}
						}
						addPoint(last, RLM_BEFORE);
						break;
					}
					if ((DirPropFlag(dirProp) & MASK_R_AL) != 0) {
						break;
					}
				}
			}
		}

		if ((reorderingOptions & OPTION_REMOVE_CONTROLS) != 0) {
			resultLength -= controlCount;
		} else {
			resultLength += insertPoints.size;
		}
		setParaSuccess();
	}

	/**
	 * Perform the Unicode Bidi algorithm. It is defined in the
	 * <a href="http://www.unicode.org/reports/tr9/">Unicode Standard Annex #9:
	 * Unicode Bidirectional Algorithm</a>, version 13, also described in The
	 * Unicode Standard, Version 4.0 .
	 * <p>
	 *
	 * This method takes a piece of plain text containing one or more paragraphs,
	 * with or without externally specified embedding levels from <i>styled</i> text
	 * and computes the left-right-directionality of each character.
	 * <p>
	 *
	 * If the entire text is all of the same directionality, then the method may not
	 * perform all the steps described by the algorithm, i.e., some levels may not
	 * be the same as if all steps were performed. This is not relevant for
	 * unidirectional text.<br>
	 * For example, in pure LTR text with numbers the numbers would get a resolved
	 * level of 2 higher than the surrounding text according to the algorithm. This
	 * implementation may set all resolved levels to the same value in such a case.
	 * <p>
	 *
	 * The text can be composed of multiple paragraphs. Occurrence of a block
	 * separator in the text terminates a paragraph, and whatever comes next starts
	 * a new paragraph. The exception to this rule is when a Carriage Return (CR) is
	 * followed by a Line Feed (LF). Both CR and LF are block separators, but in
	 * that case, the pair of characters is considered as terminating the preceding
	 * paragraph, and a new paragraph will be started by a character coming after
	 * the LF.
	 *
	 * Although the text is passed here as a <code>String</code>, it is stored
	 * internally as an array of characters. Therefore the documentation will refer
	 * to indexes of the characters in the text.
	 *
	 * @param text            contains the text that the Bidi algorithm will be
	 *                        performed on. This text can be retrieved with
	 *                        <code>getText()</code> or
	 *                        <code>getTextAsString</code>.<br>
	 *
	 * @param paraLevel       specifies the default level for the text; it is
	 *                        typically 0 (LTR) or 1 (RTL). If the method shall
	 *                        determine the paragraph level from the text, then
	 *                        <code>paraLevel</code> can be set to either
	 *                        <code>LEVEL_DEFAULT_LTR</code> or
	 *                        <code>LEVEL_DEFAULT_RTL</code>; if the text contains
	 *                        multiple paragraphs, the paragraph level shall be
	 *                        determined separately for each paragraph; if a
	 *                        paragraph does not include any strongly typed
	 *                        character, then the desired default is used (0 for LTR
	 *                        or 1 for RTL). Any other value between 0 and
	 *                        <code>MAX_EXPLICIT_LEVEL</code> is also valid, with
	 *                        odd levels indicating RTL.
	 *
	 * @param embeddingLevels (in) may be used to preset the embedding and override
	 *                        levels, ignoring characters like LRE and PDF in the
	 *                        text. A level overrides the directional property of
	 *                        its corresponding (same index) character if the level
	 *                        has the <code>LEVEL_OVERRIDE</code> bit set.<br>
	 *                        <br>
	 *                        Except for that bit, it must be
	 *                        <code>paraLevel<=embeddingLevels[]<=MAX_EXPLICIT_LEVEL</code>,
	 *                        with one exception: a level of zero may be specified
	 *                        for a paragraph separator even if
	 *                        <code>paraLevel&gt;0</code> when multiple paragraphs
	 *                        are submitted in the same call to
	 *                        <code>setPara()</code>.<br>
	 *                        <br>
	 *                        <strong>Caution: </strong>A reference to this array,
	 *                        not a copy of the levels, will be stored in the
	 *                        <code>Bidi</code> object; the
	 *                        <code>embeddingLevels</code> should not be modified to
	 *                        avoid unexpected results on subsequent Bidi
	 *                        operations. However, the <code>setPara()</code> and
	 *                        <code>setLine()</code> methods may modify some or all
	 *                        of the levels.<br>
	 *                        <br>
	 *                        <strong>Note:</strong> the
	 *                        <code>embeddingLevels</code> array must have one entry
	 *                        for each character in <code>text</code>.
	 *
	 * @throws IllegalArgumentException if the values in embeddingLevels are not
	 *                                  within the allowed range
	 *
	 * @see #LEVEL_DEFAULT_LTR
	 * @see #LEVEL_DEFAULT_RTL
	 * @see #LEVEL_OVERRIDE
	 * @see #MAX_EXPLICIT_LEVEL
	 * @stable ICU 3.8
	 */
	void setPara(String text, byte paraLevel, byte[] embeddingLevels) {
		if (text == null) {
			setPara(new char[0], paraLevel, embeddingLevels);
		} else {
			setPara(text.toCharArray(), paraLevel, embeddingLevels);
		}
	}

	void setParaRunsOnly(char[] parmText, byte parmParaLevel) {
		int[] visualMap;
		String visualText;
		int saveLength, saveTrailingWSStart;
		byte[] saveLevels;
		byte saveDirection;
		int i, j, visualStart, logicalStart, oldRunCount, runLength, addedRuns, insertRemove, start, limit, step,
				indexOddBit, logicalPos, index, index1;
		int saveOptions;

		reorderingMode = REORDER_DEFAULT;
		int parmLength = parmText.length;
		if (parmLength == 0) {
			setPara(parmText, parmParaLevel, null);
			reorderingMode = REORDER_RUNS_ONLY;
			return;
		}
		/* obtain memory for mapping table and visual text */
		saveOptions = reorderingOptions;
		if ((saveOptions & OPTION_INSERT_MARKS) > 0) {
			reorderingOptions &= ~OPTION_INSERT_MARKS;
			reorderingOptions |= OPTION_REMOVE_CONTROLS;
		}
		parmParaLevel &= 1; /* accept only 0 or 1 */
		setPara(parmText, parmParaLevel, null);
		/*
		 * we cannot access directly levels since it is not yet set if direction is not
		 * MIXED
		 */
		saveLevels = new byte[this.length];
		System.arraycopy(getLevels(), 0, saveLevels, 0, this.length);
		saveTrailingWSStart = trailingWSStart;

		/*
		 * FOOD FOR THOUGHT: instead of writing the visual text, we could use the visual
		 * map and the dirProps array to drive the second call to setPara (but must make
		 * provision for possible removal of Bidi controls. Alternatively, only use the
		 * dirProps array via customized classifier callback.
		 */
		visualText = writeReordered(DO_MIRRORING);
		visualMap = getVisualMap();
		this.reorderingOptions = saveOptions;
		saveLength = this.length;
		saveDirection = this.direction;

		this.reorderingMode = REORDER_INVERSE_LIKE_DIRECT;
		parmParaLevel ^= 1;
		setPara(visualText, parmParaLevel, null);
		BidiLine.getRuns(this);
		/* check if some runs must be split, count how many splits */
		addedRuns = 0;
		oldRunCount = this.runCount;
		visualStart = 0;
		for (i = 0; i < oldRunCount; i++, visualStart += runLength) {
			runLength = runs[i].limit - visualStart;
			if (runLength < 2) {
				continue;
			}
			logicalStart = runs[i].start;
			for (j = logicalStart + 1; j < logicalStart + runLength; j++) {
				index = visualMap[j];
				index1 = visualMap[j - 1];
				if ((Bidi_Abs(index - index1) != 1) || (saveLevels[index] != saveLevels[index1])) {
					addedRuns++;
				}
			}
		}
		if (addedRuns > 0) {
			getRunsMemory(oldRunCount + addedRuns);
			if (runCount == 1) {
				/* because we switch from UBiDi.simpleRuns to UBiDi.runs */
				runsMemory[0] = runs[0];
			} else {
				System.arraycopy(runs, 0, runsMemory, 0, runCount);
			}
			runs = runsMemory;
			runCount += addedRuns;
			for (i = oldRunCount; i < runCount; i++) {
				if (runs[i] == null) {
					runs[i] = new BidiRun(0, 0, (byte) 0);
				}
			}
		}
		/* split runs which are not consecutive in source text */
		int newI;
		for (i = oldRunCount - 1; i >= 0; i--) {
			newI = i + addedRuns;
			runLength = i == 0 ? runs[0].limit : runs[i].limit - runs[i - 1].limit;
			logicalStart = runs[i].start;
			indexOddBit = runs[i].level & 1;
			if (runLength < 2) {
				if (addedRuns > 0) {
					runs[newI].copyFrom(runs[i]);
				}
				logicalPos = visualMap[logicalStart];
				runs[newI].start = logicalPos;
				runs[newI].level = (byte) (saveLevels[logicalPos] ^ indexOddBit);
				continue;
			}
			if (indexOddBit > 0) {
				start = logicalStart;
				limit = logicalStart + runLength - 1;
				step = 1;
			} else {
				start = logicalStart + runLength - 1;
				limit = logicalStart;
				step = -1;
			}
			for (j = start; j != limit; j += step) {
				index = visualMap[j];
				index1 = visualMap[j + step];
				if ((Bidi_Abs(index - index1) != 1) || (saveLevels[index] != saveLevels[index1])) {
					logicalPos = Bidi_Min(visualMap[start], index);
					runs[newI].start = logicalPos;
					runs[newI].level = (byte) (saveLevels[logicalPos] ^ indexOddBit);
					runs[newI].limit = runs[i].limit;
					runs[i].limit -= Bidi_Abs(j - start) + 1;
					insertRemove = runs[i].insertRemove & (LRM_AFTER | RLM_AFTER);
					runs[newI].insertRemove = insertRemove;
					runs[i].insertRemove &= ~insertRemove;
					start = j + step;
					addedRuns--;
					newI--;
				}
			}
			if (addedRuns > 0) {
				runs[newI].copyFrom(runs[i]);
			}
			logicalPos = Bidi_Min(visualMap[start], visualMap[limit]);
			runs[newI].start = logicalPos;
			runs[newI].level = (byte) (saveLevels[logicalPos] ^ indexOddBit);
		}

		cleanup1:
		/* restore initial paraLevel */
		this.paraLevel ^= 1;
		cleanup2:
		/* restore real text */
		this.text = parmText;
		this.length = saveLength;
		this.originalLength = parmLength;
		this.direction = saveDirection;
		this.levels = saveLevels;
		this.trailingWSStart = saveTrailingWSStart;
		if (runCount > 1) {
			this.direction = MIXED;
		}
		cleanup3: this.reorderingMode = REORDER_RUNS_ONLY;
	}

	private void setParaSuccess() {
		paraBidi = this; /* mark successful setPara */
	}

	boolean testDirPropFlagAt(int flag, int index) {
		return ((DirPropFlag(dirProps[index]) & flag) != 0);
	}

	/**
	 * Display the bidi internal state, used in debugging.
	 */
	@Override
	public String toString() {
		StringBuilder buf = new StringBuilder(getClass().getName());

		buf.append("[dir: ");
		buf.append(direction);
		buf.append(" baselevel: ");
		buf.append(paraLevel);
		buf.append(" length: ");
		buf.append(length);
		buf.append(" runs: ");
		if (levels == null) {
			buf.append("none");
		} else {
			buf.append('[');
			buf.append(levels[0]);
			for (int i = 1; i < levels.length; i++) {
				buf.append(' ');
				buf.append(levels[i]);
			}
			buf.append(']');
		}
		buf.append(" text: [0x");
		buf.append(Integer.toHexString(text[0]));
		for (int i = 1; i < text.length; i++) {
			buf.append(" 0x");
			buf.append(Integer.toHexString(text[i]));
		}
		buf.append("]]");

		return buf.toString();
	}

	void verifyRange(int index, int start, int limit) {
		if (index < start || index >= limit) {
			throw new IllegalArgumentException("Value " + index + " is out of range " + start + " to " + limit);
		}
	}

	void verifyValidPara() {
		if (!(this == this.paraBidi)) {
			throw new IllegalStateException();
		}
	}

	void verifyValidParaOrLine() {
		BidiBase para = this.paraBidi;
		/* verify Para */
		if (this == para) {
			return;
		}
		/* verify Line */
		if ((para == null) || (para != para.paraBidi)) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Take a <code>Bidi</code> object containing the reordering information for a
	 * piece of text (one or more paragraphs) set by <code>setPara()</code> or for a
	 * line of text set by <code>setLine()</code> and return a string containing the
	 * reordered text.
	 *
	 * <p>
	 * The text may have been aliased (only a reference was stored without copying
	 * the contents), thus it must not have been modified since the
	 * <code>setPara()</code> call.
	 * </p>
	 *
	 * This method preserves the integrity of characters with multiple code units
	 * and (optionally) combining characters. Characters in RTL runs can be replaced
	 * by mirror-image characters in the returned string. Note that "real" mirroring
	 * has to be done in a rendering engine by glyph selection and that for many
	 * "mirrored" characters there are no Unicode characters as mirror-image
	 * equivalents. There are also options to insert or remove Bidi control
	 * characters; see the descriptions of the return value and the
	 * <code>options</code> parameter, and of the option bit flags.
	 *
	 * @param options A bit set of options for the reordering that control how the
	 *                reordered text is written. The options include mirroring the
	 *                characters on a code point basis and inserting LRM characters,
	 *                which is used especially for transforming visually stored text
	 *                to logically stored text (although this is still an imperfect
	 *                implementation of an "inverse Bidi" algorithm because it uses
	 *                the "forward Bidi" algorithm at its core). The available
	 *                options are: <code>DO_MIRRORING</code>,
	 *                <code>INSERT_LRM_FOR_NUMERIC</code>,
	 *                <code>KEEP_BASE_COMBINING</code>, <code>OUTPUT_REVERSE</code>,
	 *                <code>REMOVE_BIDI_CONTROLS</code>, <code>STREAMING</code>
	 *
	 * @return The reordered text. If the <code>INSERT_LRM_FOR_NUMERIC</code> option
	 *         is set, then the length of the returned string could be as large as
	 *         <code>getLength()+2*countRuns()</code>.<br>
	 *         If the <code>REMOVE_BIDI_CONTROLS</code> option is set, then the
	 *         length of the returned string may be less than
	 *         <code>getLength()</code>.<br>
	 *         If none of these options is set, then the length of the returned
	 *         string will be exactly <code>getProcessedLength()</code>.
	 *
	 * @throws IllegalStateException if this call is not preceded by a successful
	 *                               call to <code>setPara</code> or
	 *                               <code>setLine</code>
	 *
	 * @see #DO_MIRRORING
	 * @see #INSERT_LRM_FOR_NUMERIC
	 * @see #KEEP_BASE_COMBINING
	 * @see #OUTPUT_REVERSE
	 * @see #REMOVE_BIDI_CONTROLS
	 * @see #OPTION_STREAMING
	 * @see #getProcessedLength
	 * @stable ICU 3.8
	 */
	public String writeReordered(int options) {
		verifyValidParaOrLine();
		if (length == 0) {
			/* nothing to do */
			return "";
		}
		return BidiWriter.writeReordered(this, options);
	}

}
