--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.base/share/classes/sun/util/locale/provider/RuleBasedBreakIterator.java Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,1195 @@
+/*
+ * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ *
+ * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
+ * (C) Copyright IBM Corp. 1996 - 2002 - All Rights Reserved
+ *
+ * The original version of this source code and documentation
+ * is copyrighted and owned by Taligent, Inc., a wholly-owned
+ * subsidiary of IBM. These materials are provided under terms
+ * of a License Agreement between Taligent and Sun. This technology
+ * is protected by multiple US and International patents.
+ *
+ * This notice and attribution to Taligent may not be removed.
+ * Taligent is a registered trademark of Taligent, Inc.
+ */
+
+package sun.util.locale.provider;
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.security.AccessController;
+import java.security.PrivilegedActionException;
+import java.security.PrivilegedExceptionAction;
+import java.text.BreakIterator;
+import java.text.CharacterIterator;
+import java.text.StringCharacterIterator;
+import java.util.MissingResourceException;
+import sun.text.CompactByteArray;
+import sun.text.SupplementaryCharacterData;
+
+/**
+ * <p>A subclass of BreakIterator whose behavior is specified using a list of rules.</p>
+ *
+ * <p>There are two kinds of rules, which are separated by semicolons: <i>substitutions</i>
+ * and <i>regular expressions.</i></p>
+ *
+ * <p>A substitution rule defines a name that can be used in place of an expression. It
+ * consists of a name, which is a string of characters contained in angle brackets, an equals
+ * sign, and an expression. (There can be no whitespace on either side of the equals sign.)
+ * To keep its syntactic meaning intact, the expression must be enclosed in parentheses or
+ * square brackets. A substitution is visible after its definition, and is filled in using
+ * simple textual substitution. Substitution definitions can contain other substitutions, as
+ * long as those substitutions have been defined first. Substitutions are generally used to
+ * make the regular expressions (which can get quite complex) shorted and easier to read.
+ * They typically define either character categories or commonly-used subexpressions.</p>
+ *
+ * <p>There is one special substitution. If the description defines a substitution
+ * called "<ignore>", the expression must be a [] expression, and the
+ * expression defines a set of characters (the "<em>ignore characters</em>") that
+ * will be transparent to the BreakIterator. A sequence of characters will break the
+ * same way it would if any ignore characters it contains are taken out. Break
+ * positions never occur befoer ignore characters.</p>
+ *
+ * <p>A regular expression uses a subset of the normal Unix regular-expression syntax, and
+ * defines a sequence of characters to be kept together. With one significant exception, the
+ * iterator uses a longest-possible-match algorithm when matching text to regular
+ * expressions. The iterator also treats descriptions containing multiple regular expressions
+ * as if they were ORed together (i.e., as if they were separated by |).</p>
+ *
+ * <p>The special characters recognized by the regular-expression parser are as follows:</p>
+ *
+ * <blockquote>
+ * <table border="1" width="100%">
+ * <tr>
+ * <td width="6%">*</td>
+ * <td width="94%">Specifies that the expression preceding the asterisk may occur any number
+ * of times (including not at all).</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">{}</td>
+ * <td width="94%">Encloses a sequence of characters that is optional.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">()</td>
+ * <td width="94%">Encloses a sequence of characters. If followed by *, the sequence
+ * repeats. Otherwise, the parentheses are just a grouping device and a way to delimit
+ * the ends of expressions containing |.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">|</td>
+ * <td width="94%">Separates two alternative sequences of characters. Either one
+ * sequence or the other, but not both, matches this expression. The | character can
+ * only occur inside ().</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">.</td>
+ * <td width="94%">Matches any character.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">*?</td>
+ * <td width="94%">Specifies a non-greedy asterisk. *? works the same way as *, except
+ * when there is overlap between the last group of characters in the expression preceding the
+ * * and the first group of characters following the *. When there is this kind of
+ * overlap, * will match the longest sequence of characters that match the expression before
+ * the *, and *? will match the shortest sequence of characters matching the expression
+ * before the *?. For example, if you have "xxyxyyyxyxyxxyxyxyy" in the text,
+ * "x[xy]*x" will match through to the last x (i.e., "<strong>xxyxyyyxyxyxxyxyx</strong>yy",
+ * but "x[xy]*?x" will only match the first two xes ("<strong>xx</strong>yxyyyxyxyxxyxyxyy").</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">[]</td>
+ * <td width="94%">Specifies a group of alternative characters. A [] expression will
+ * match any single character that is specified in the [] expression. For more on the
+ * syntax of [] expressions, see below.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">/</td>
+ * <td width="94%">Specifies where the break position should go if text matches this
+ * expression. (e.g., "[a-z]*/[:Zs:]*[1-0]" will match if the iterator sees a run
+ * of letters, followed by a run of whitespace, followed by a digit, but the break position
+ * will actually go before the whitespace). Expressions that don't contain / put the
+ * break position at the end of the matching text.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">\</td>
+ * <td width="94%">Escape character. The \ itself is ignored, but causes the next
+ * character to be treated as literal character. This has no effect for many
+ * characters, but for the characters listed above, this deprives them of their special
+ * meaning. (There are no special escape sequences for Unicode characters, or tabs and
+ * newlines; these are all handled by a higher-level protocol. In a Java string,
+ * "\n" will be converted to a literal newline character by the time the
+ * regular-expression parser sees it. Of course, this means that \ sequences that are
+ * visible to the regexp parser must be written as \\ when inside a Java string.) All
+ * characters in the ASCII range except for letters, digits, and control characters are
+ * reserved characters to the parser and must be preceded by \ even if they currently don't
+ * mean anything.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">!</td>
+ * <td width="94%">If ! appears at the beginning of a regular expression, it tells the regexp
+ * parser that this expression specifies the backwards-iteration behavior of the iterator,
+ * and not its normal iteration behavior. This is generally only used in situations
+ * where the automatically-generated backwards-iteration brhavior doesn't produce
+ * satisfactory results and must be supplemented with extra client-specified rules.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%"><em>(all others)</em></td>
+ * <td width="94%">All other characters are treated as literal characters, which must match
+ * the corresponding character(s) in the text exactly.</td>
+ * </tr>
+ * </table>
+ * </blockquote>
+ *
+ * <p>Within a [] expression, a number of other special characters can be used to specify
+ * groups of characters:</p>
+ *
+ * <blockquote>
+ * <table border="1" width="100%">
+ * <tr>
+ * <td width="6%">-</td>
+ * <td width="94%">Specifies a range of matching characters. For example
+ * "[a-p]" matches all lowercase Latin letters from a to p (inclusive). The -
+ * sign specifies ranges of continuous Unicode numeric values, not ranges of characters in a
+ * language's alphabetical order: "[a-z]" doesn't include capital letters, nor does
+ * it include accented letters such as a-umlaut.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">::</td>
+ * <td width="94%">A pair of colons containing a one- or two-letter code matches all
+ * characters in the corresponding Unicode category. The two-letter codes are the same
+ * as the two-letter codes in the Unicode database (for example, "[:Sc::Sm:]"
+ * matches all currency symbols and all math symbols). Specifying a one-letter code is
+ * the same as specifying all two-letter codes that begin with that letter (for example,
+ * "[:L:]" matches all letters, and is equivalent to
+ * "[:Lu::Ll::Lo::Lm::Lt:]"). Anything other than a valid two-letter Unicode
+ * category code or a single letter that begins a Unicode category code is illegal within
+ * colons.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">[]</td>
+ * <td width="94%">[] expressions can nest. This has no effect, except when used in
+ * conjunction with the ^ token.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%">^</td>
+ * <td width="94%">Excludes the character (or the characters in the [] expression) following
+ * it from the group of characters. For example, "[a-z^p]" matches all Latin
+ * lowercase letters except p. "[:L:^[\u4e00-\u9fff]]" matches all letters
+ * except the Han ideographs.</td>
+ * </tr>
+ * <tr>
+ * <td width="6%"><em>(all others)</em></td>
+ * <td width="94%">All other characters are treated as literal characters. (For
+ * example, "[aeiou]" specifies just the letters a, e, i, o, and u.)</td>
+ * </tr>
+ * </table>
+ * </blockquote>
+ *
+ * <p>For a more complete explanation, see <a
+ * href="http://www.ibm.com/java/education/boundaries/boundaries.html">http://www.ibm.com/java/education/boundaries/boundaries.html</a>.
+ * For examples, see the resource data (which is annotated).</p>
+ *
+ * @author Richard Gillam
+ */
+class RuleBasedBreakIterator extends BreakIterator {
+
+ /**
+ * A token used as a character-category value to identify ignore characters
+ */
+ protected static final byte IGNORE = -1;
+
+ /**
+ * The state number of the starting state
+ */
+ private static final short START_STATE = 1;
+
+ /**
+ * The state-transition value indicating "stop"
+ */
+ private static final short STOP_STATE = 0;
+
+ /**
+ * Magic number for the BreakIterator data file format.
+ */
+ static final byte[] LABEL = {
+ (byte)'B', (byte)'I', (byte)'d', (byte)'a', (byte)'t', (byte)'a',
+ (byte)'\0'
+ };
+ static final int LABEL_LENGTH = LABEL.length;
+
+ /**
+ * Version number of the dictionary that was read in.
+ */
+ static final byte supportedVersion = 1;
+
+ /**
+ * Header size in byte count
+ */
+ private static final int HEADER_LENGTH = 36;
+
+ /**
+ * An array length of indices for BMP characters
+ */
+ private static final int BMP_INDICES_LENGTH = 512;
+
+ /**
+ * Tables that indexes from character values to character category numbers
+ */
+ private CompactByteArray charCategoryTable = null;
+ private SupplementaryCharacterData supplementaryCharCategoryTable = null;
+
+ /**
+ * The table of state transitions used for forward iteration
+ */
+ private short[] stateTable = null;
+
+ /**
+ * The table of state transitions used to sync up the iterator with the
+ * text in backwards and random-access iteration
+ */
+ private short[] backwardsStateTable = null;
+
+ /**
+ * A list of flags indicating which states in the state table are accepting
+ * ("end") states
+ */
+ private boolean[] endStates = null;
+
+ /**
+ * A list of flags indicating which states in the state table are
+ * lookahead states (states which turn lookahead on and off)
+ */
+ private boolean[] lookaheadStates = null;
+
+ /**
+ * A table for additional data. May be used by a subclass of
+ * RuleBasedBreakIterator.
+ */
+ private byte[] additionalData = null;
+
+ /**
+ * The number of character categories (and, thus, the number of columns in
+ * the state tables)
+ */
+ private int numCategories;
+
+ /**
+ * The character iterator through which this BreakIterator accesses the text
+ */
+ private CharacterIterator text = null;
+
+ /**
+ * A CRC32 value of all data in datafile
+ */
+ private long checksum;
+
+ //=======================================================================
+ // constructors
+ //=======================================================================
+
+ /**
+ * Constructs a RuleBasedBreakIterator according to the datafile
+ * provided.
+ */
+ RuleBasedBreakIterator(String datafile)
+ throws IOException, MissingResourceException {
+ readTables(datafile);
+ }
+
+ /**
+ * Read datafile. The datafile's format is as follows:
+ * <pre>
+ * BreakIteratorData {
+ * u1 magic[7];
+ * u1 version;
+ * u4 totalDataSize;
+ * header_info header;
+ * body value;
+ * }
+ * </pre>
+ * <code>totalDataSize</code> is the summation of the size of
+ * <code>header_info</code> and <code>body</code> in byte count.
+ * <p>
+ * In <code>header</code>, each field except for checksum implies the
+ * length of each field. Since <code>BMPdataLength</code> is a fixed-length
+ * data(512 entries), its length isn't included in <code>header</code>.
+ * <code>checksum</code> is a CRC32 value of all in <code>body</code>.
+ * <pre>
+ * header_info {
+ * u4 stateTableLength;
+ * u4 backwardsStateTableLength;
+ * u4 endStatesLength;
+ * u4 lookaheadStatesLength;
+ * u4 BMPdataLength;
+ * u4 nonBMPdataLength;
+ * u4 additionalDataLength;
+ * u8 checksum;
+ * }
+ * </pre>
+ * <p>
+ *
+ * Finally, <code>BMPindices</code> and <code>BMPdata</code> are set to
+ * <code>charCategoryTable</code>. <code>nonBMPdata</code> is set to
+ * <code>supplementaryCharCategoryTable</code>.
+ * <pre>
+ * body {
+ * u2 stateTable[stateTableLength];
+ * u2 backwardsStateTable[backwardsStateTableLength];
+ * u1 endStates[endStatesLength];
+ * u1 lookaheadStates[lookaheadStatesLength];
+ * u2 BMPindices[512];
+ * u1 BMPdata[BMPdataLength];
+ * u4 nonBMPdata[numNonBMPdataLength];
+ * u1 additionalData[additionalDataLength];
+ * }
+ * </pre>
+ */
+ protected final void readTables(String datafile)
+ throws IOException, MissingResourceException {
+
+ byte[] buffer = readFile(datafile);
+
+ /* Read header_info. */
+ int stateTableLength = getInt(buffer, 0);
+ int backwardsStateTableLength = getInt(buffer, 4);
+ int endStatesLength = getInt(buffer, 8);
+ int lookaheadStatesLength = getInt(buffer, 12);
+ int BMPdataLength = getInt(buffer, 16);
+ int nonBMPdataLength = getInt(buffer, 20);
+ int additionalDataLength = getInt(buffer, 24);
+ checksum = getLong(buffer, 28);
+
+ /* Read stateTable[numCategories * numRows] */
+ stateTable = new short[stateTableLength];
+ int offset = HEADER_LENGTH;
+ for (int i = 0; i < stateTableLength; i++, offset+=2) {
+ stateTable[i] = getShort(buffer, offset);
+ }
+
+ /* Read backwardsStateTable[numCategories * numRows] */
+ backwardsStateTable = new short[backwardsStateTableLength];
+ for (int i = 0; i < backwardsStateTableLength; i++, offset+=2) {
+ backwardsStateTable[i] = getShort(buffer, offset);
+ }
+
+ /* Read endStates[numRows] */
+ endStates = new boolean[endStatesLength];
+ for (int i = 0; i < endStatesLength; i++, offset++) {
+ endStates[i] = buffer[offset] == 1;
+ }
+
+ /* Read lookaheadStates[numRows] */
+ lookaheadStates = new boolean[lookaheadStatesLength];
+ for (int i = 0; i < lookaheadStatesLength; i++, offset++) {
+ lookaheadStates[i] = buffer[offset] == 1;
+ }
+
+ /* Read a category table and indices for BMP characters. */
+ short[] temp1 = new short[BMP_INDICES_LENGTH]; // BMPindices
+ for (int i = 0; i < BMP_INDICES_LENGTH; i++, offset+=2) {
+ temp1[i] = getShort(buffer, offset);
+ }
+ byte[] temp2 = new byte[BMPdataLength]; // BMPdata
+ System.arraycopy(buffer, offset, temp2, 0, BMPdataLength);
+ offset += BMPdataLength;
+ charCategoryTable = new CompactByteArray(temp1, temp2);
+
+ /* Read a category table for non-BMP characters. */
+ int[] temp3 = new int[nonBMPdataLength];
+ for (int i = 0; i < nonBMPdataLength; i++, offset+=4) {
+ temp3[i] = getInt(buffer, offset);
+ }
+ supplementaryCharCategoryTable = new SupplementaryCharacterData(temp3);
+
+ /* Read additional data */
+ if (additionalDataLength > 0) {
+ additionalData = new byte[additionalDataLength];
+ System.arraycopy(buffer, offset, additionalData, 0, additionalDataLength);
+ }
+
+ /* Set numCategories */
+ numCategories = stateTable.length / endStates.length;
+ }
+
+ protected byte[] readFile(final String datafile)
+ throws IOException, MissingResourceException {
+
+ BufferedInputStream is;
+ try {
+ is = AccessController.doPrivileged(
+ new PrivilegedExceptionAction<BufferedInputStream>() {
+ @Override
+ public BufferedInputStream run() throws Exception {
+ return new BufferedInputStream(getClass().getResourceAsStream("/sun/text/resources/" + datafile));
+ }
+ }
+ );
+ }
+ catch (PrivilegedActionException e) {
+ throw new InternalError(e.toString(), e);
+ }
+
+ int offset = 0;
+
+ /* First, read magic, version, and header_info. */
+ int len = LABEL_LENGTH + 5;
+ byte[] buf = new byte[len];
+ if (is.read(buf) != len) {
+ throw new MissingResourceException("Wrong header length",
+ datafile, "");
+ }
+
+ /* Validate the magic number. */
+ for (int i = 0; i < LABEL_LENGTH; i++, offset++) {
+ if (buf[offset] != LABEL[offset]) {
+ throw new MissingResourceException("Wrong magic number",
+ datafile, "");
+ }
+ }
+
+ /* Validate the version number. */
+ if (buf[offset] != supportedVersion) {
+ throw new MissingResourceException("Unsupported version(" + buf[offset] + ")",
+ datafile, "");
+ }
+
+ /* Read data: totalDataSize + 8(for checksum) */
+ len = getInt(buf, ++offset);
+ buf = new byte[len];
+ if (is.read(buf) != len) {
+ throw new MissingResourceException("Wrong data length",
+ datafile, "");
+ }
+
+ is.close();
+
+ return buf;
+ }
+
+ byte[] getAdditionalData() {
+ return additionalData;
+ }
+
+ void setAdditionalData(byte[] b) {
+ additionalData = b;
+ }
+
+ //=======================================================================
+ // boilerplate
+ //=======================================================================
+ /**
+ * Clones this iterator.
+ * @return A newly-constructed RuleBasedBreakIterator with the same
+ * behavior as this one.
+ */
+ @Override
+ public Object clone() {
+ RuleBasedBreakIterator result = (RuleBasedBreakIterator) super.clone();
+ if (text != null) {
+ result.text = (CharacterIterator) text.clone();
+ }
+ return result;
+ }
+
+ /**
+ * Returns true if both BreakIterators are of the same class, have the same
+ * rules, and iterate over the same text.
+ */
+ @Override
+ public boolean equals(Object that) {
+ try {
+ if (that == null) {
+ return false;
+ }
+
+ RuleBasedBreakIterator other = (RuleBasedBreakIterator) that;
+ if (checksum != other.checksum) {
+ return false;
+ }
+ if (text == null) {
+ return other.text == null;
+ } else {
+ return text.equals(other.text);
+ }
+ }
+ catch(ClassCastException e) {
+ return false;
+ }
+ }
+
+ /**
+ * Returns text
+ */
+ @Override
+ public String toString() {
+ StringBuilder sb = new StringBuilder();
+ sb.append('[');
+ sb.append("checksum=0x");
+ sb.append(Long.toHexString(checksum));
+ sb.append(']');
+ return sb.toString();
+ }
+
+ /**
+ * Compute a hashcode for this BreakIterator
+ * @return A hash code
+ */
+ @Override
+ public int hashCode() {
+ return (int)checksum;
+ }
+
+ //=======================================================================
+ // BreakIterator overrides
+ //=======================================================================
+
+ /**
+ * Sets the current iteration position to the beginning of the text.
+ * (i.e., the CharacterIterator's starting offset).
+ * @return The offset of the beginning of the text.
+ */
+ @Override
+ public int first() {
+ CharacterIterator t = getText();
+
+ t.first();
+ return t.getIndex();
+ }
+
+ /**
+ * Sets the current iteration position to the end of the text.
+ * (i.e., the CharacterIterator's ending offset).
+ * @return The text's past-the-end offset.
+ */
+ @Override
+ public int last() {
+ CharacterIterator t = getText();
+
+ // I'm not sure why, but t.last() returns the offset of the last character,
+ // rather than the past-the-end offset
+ t.setIndex(t.getEndIndex());
+ return t.getIndex();
+ }
+
+ /**
+ * Advances the iterator either forward or backward the specified number of steps.
+ * Negative values move backward, and positive values move forward. This is
+ * equivalent to repeatedly calling next() or previous().
+ * @param n The number of steps to move. The sign indicates the direction
+ * (negative is backwards, and positive is forwards).
+ * @return The character offset of the boundary position n boundaries away from
+ * the current one.
+ */
+ @Override
+ public int next(int n) {
+ int result = current();
+ while (n > 0) {
+ result = handleNext();
+ --n;
+ }
+ while (n < 0) {
+ result = previous();
+ ++n;
+ }
+ return result;
+ }
+
+ /**
+ * Advances the iterator to the next boundary position.
+ * @return The position of the first boundary after this one.
+ */
+ @Override
+ public int next() {
+ return handleNext();
+ }
+
+ private int cachedLastKnownBreak = BreakIterator.DONE;
+
+ /**
+ * Advances the iterator backwards, to the last boundary preceding this one.
+ * @return The position of the last boundary position preceding this one.
+ */
+ @Override
+ public int previous() {
+ // if we're already sitting at the beginning of the text, return DONE
+ CharacterIterator text = getText();
+ if (current() == text.getBeginIndex()) {
+ return BreakIterator.DONE;
+ }
+
+ // set things up. handlePrevious() will back us up to some valid
+ // break position before the current position (we back our internal
+ // iterator up one step to prevent handlePrevious() from returning
+ // the current position), but not necessarily the last one before
+ // where we started
+ int start = current();
+ int lastResult = cachedLastKnownBreak;
+ if (lastResult >= start || lastResult <= BreakIterator.DONE) {
+ getPrevious();
+ lastResult = handlePrevious();
+ } else {
+ //it might be better to check if handlePrevious() give us closer
+ //safe value but handlePrevious() is slow too
+ //So, this has to be done carefully
+ text.setIndex(lastResult);
+ }
+ int result = lastResult;
+
+ // iterate forward from the known break position until we pass our
+ // starting point. The last break position before the starting
+ // point is our return value
+ while (result != BreakIterator.DONE && result < start) {
+ lastResult = result;
+ result = handleNext();
+ }
+
+ // set the current iteration position to be the last break position
+ // before where we started, and then return that value
+ text.setIndex(lastResult);
+ cachedLastKnownBreak = lastResult;
+ return lastResult;
+ }
+
+ /**
+ * Returns previous character
+ */
+ private int getPrevious() {
+ char c2 = text.previous();
+ if (Character.isLowSurrogate(c2) &&
+ text.getIndex() > text.getBeginIndex()) {
+ char c1 = text.previous();
+ if (Character.isHighSurrogate(c1)) {
+ return Character.toCodePoint(c1, c2);
+ } else {
+ text.next();
+ }
+ }
+ return (int)c2;
+ }
+
+ /**
+ * Returns current character
+ */
+ int getCurrent() {
+ char c1 = text.current();
+ if (Character.isHighSurrogate(c1) &&
+ text.getIndex() < text.getEndIndex()) {
+ char c2 = text.next();
+ text.previous();
+ if (Character.isLowSurrogate(c2)) {
+ return Character.toCodePoint(c1, c2);
+ }
+ }
+ return (int)c1;
+ }
+
+ /**
+ * Returns the count of next character.
+ */
+ private int getCurrentCodePointCount() {
+ char c1 = text.current();
+ if (Character.isHighSurrogate(c1) &&
+ text.getIndex() < text.getEndIndex()) {
+ char c2 = text.next();
+ text.previous();
+ if (Character.isLowSurrogate(c2)) {
+ return 2;
+ }
+ }
+ return 1;
+ }
+
+ /**
+ * Returns next character
+ */
+ int getNext() {
+ int index = text.getIndex();
+ int endIndex = text.getEndIndex();
+ if (index == endIndex ||
+ (index += getCurrentCodePointCount()) >= endIndex) {
+ return CharacterIterator.DONE;
+ }
+ text.setIndex(index);
+ return getCurrent();
+ }
+
+ /**
+ * Returns the position of next character.
+ */
+ private int getNextIndex() {
+ int index = text.getIndex() + getCurrentCodePointCount();
+ int endIndex = text.getEndIndex();
+ if (index > endIndex) {
+ return endIndex;
+ } else {
+ return index;
+ }
+ }
+
+ /**
+ * Throw IllegalArgumentException unless begin <= offset < end.
+ */
+ protected static final void checkOffset(int offset, CharacterIterator text) {
+ if (offset < text.getBeginIndex() || offset > text.getEndIndex()) {
+ throw new IllegalArgumentException("offset out of bounds");
+ }
+ }
+
+ /**
+ * Sets the iterator to refer to the first boundary position following
+ * the specified position.
+ * @offset The position from which to begin searching for a break position.
+ * @return The position of the first break after the current position.
+ */
+ @Override
+ public int following(int offset) {
+
+ CharacterIterator text = getText();
+ checkOffset(offset, text);
+
+ // Set our internal iteration position (temporarily)
+ // to the position passed in. If this is the _beginning_ position,
+ // then we can just use next() to get our return value
+ text.setIndex(offset);
+ if (offset == text.getBeginIndex()) {
+ cachedLastKnownBreak = handleNext();
+ return cachedLastKnownBreak;
+ }
+
+ // otherwise, we have to sync up first. Use handlePrevious() to back
+ // us up to a known break position before the specified position (if
+ // we can determine that the specified position is a break position,
+ // we don't back up at all). This may or may not be the last break
+ // position at or before our starting position. Advance forward
+ // from here until we've passed the starting position. The position
+ // we stop on will be the first break position after the specified one.
+ int result = cachedLastKnownBreak;
+ if (result >= offset || result <= BreakIterator.DONE) {
+ result = handlePrevious();
+ } else {
+ //it might be better to check if handlePrevious() give us closer
+ //safe value but handlePrevious() is slow too
+ //So, this has to be done carefully
+ text.setIndex(result);
+ }
+ while (result != BreakIterator.DONE && result <= offset) {
+ result = handleNext();
+ }
+ cachedLastKnownBreak = result;
+ return result;
+ }
+
+ /**
+ * Sets the iterator to refer to the last boundary position before the
+ * specified position.
+ * @offset The position to begin searching for a break from.
+ * @return The position of the last boundary before the starting position.
+ */
+ @Override
+ public int preceding(int offset) {
+ // if we start by updating the current iteration position to the
+ // position specified by the caller, we can just use previous()
+ // to carry out this operation
+ CharacterIterator text = getText();
+ checkOffset(offset, text);
+ text.setIndex(offset);
+ return previous();
+ }
+
+ /**
+ * Returns true if the specified position is a boundary position. As a side
+ * effect, leaves the iterator pointing to the first boundary position at
+ * or after "offset".
+ * @param offset the offset to check.
+ * @return True if "offset" is a boundary position.
+ */
+ @Override
+ public boolean isBoundary(int offset) {
+ CharacterIterator text = getText();
+ checkOffset(offset, text);
+ if (offset == text.getBeginIndex()) {
+ return true;
+ }
+
+ // to check whether this is a boundary, we can use following() on the
+ // position before the specified one and return true if the position we
+ // get back is the one the user specified
+ else {
+ return following(offset - 1) == offset;
+ }
+ }
+
+ /**
+ * Returns the current iteration position.
+ * @return The current iteration position.
+ */
+ @Override
+ public int current() {
+ return getText().getIndex();
+ }
+
+ /**
+ * Return a CharacterIterator over the text being analyzed. This version
+ * of this method returns the actual CharacterIterator we're using internally.
+ * Changing the state of this iterator can have undefined consequences. If
+ * you need to change it, clone it first.
+ * @return An iterator over the text being analyzed.
+ */
+ @Override
+ public CharacterIterator getText() {
+ // The iterator is initialized pointing to no text at all, so if this
+ // function is called while we're in that state, we have to fudge an
+ // iterator to return.
+ if (text == null) {
+ text = new StringCharacterIterator("");
+ }
+ return text;
+ }
+
+ /**
+ * Set the iterator to analyze a new piece of text. This function resets
+ * the current iteration position to the beginning of the text.
+ * @param newText An iterator over the text to analyze.
+ */
+ @Override
+ public void setText(CharacterIterator newText) {
+ // Test iterator to see if we need to wrap it in a SafeCharIterator.
+ // The correct behavior for CharacterIterators is to allow the
+ // position to be set to the endpoint of the iterator. Many
+ // CharacterIterators do not uphold this, so this is a workaround
+ // to permit them to use this class.
+ int end = newText.getEndIndex();
+ boolean goodIterator;
+ try {
+ newText.setIndex(end); // some buggy iterators throw an exception here
+ goodIterator = newText.getIndex() == end;
+ }
+ catch(IllegalArgumentException e) {
+ goodIterator = false;
+ }
+
+ if (goodIterator) {
+ text = newText;
+ }
+ else {
+ text = new SafeCharIterator(newText);
+ }
+ text.first();
+
+ cachedLastKnownBreak = BreakIterator.DONE;
+ }
+
+
+ //=======================================================================
+ // implementation
+ //=======================================================================
+
+ /**
+ * This method is the actual implementation of the next() method. All iteration
+ * vectors through here. This method initializes the state machine to state 1
+ * and advances through the text character by character until we reach the end
+ * of the text or the state machine transitions to state 0. We update our return
+ * value every time the state machine passes through a possible end state.
+ */
+ protected int handleNext() {
+ // if we're already at the end of the text, return DONE.
+ CharacterIterator text = getText();
+ if (text.getIndex() == text.getEndIndex()) {
+ return BreakIterator.DONE;
+ }
+
+ // no matter what, we always advance at least one character forward
+ int result = getNextIndex();
+ int lookaheadResult = 0;
+
+ // begin in state 1
+ int state = START_STATE;
+ int category;
+ int c = getCurrent();
+
+ // loop until we reach the end of the text or transition to state 0
+ while (c != CharacterIterator.DONE && state != STOP_STATE) {
+
+ // look up the current character's character category (which tells us
+ // which column in the state table to look at)
+ category = lookupCategory(c);
+
+ // if the character isn't an ignore character, look up a state
+ // transition in the state table
+ if (category != IGNORE) {
+ state = lookupState(state, category);
+ }
+
+ // if the state we've just transitioned to is a lookahead state,
+ // (but not also an end state), save its position. If it's
+ // both a lookahead state and an end state, update the break position
+ // to the last saved lookup-state position
+ if (lookaheadStates[state]) {
+ if (endStates[state]) {
+ result = lookaheadResult;
+ }
+ else {
+ lookaheadResult = getNextIndex();
+ }
+ }
+
+ // otherwise, if the state we've just transitioned to is an accepting
+ // state, update the break position to be the current iteration position
+ else {
+ if (endStates[state]) {
+ result = getNextIndex();
+ }
+ }
+
+ c = getNext();
+ }
+
+ // if we've run off the end of the text, and the very last character took us into
+ // a lookahead state, advance the break position to the lookahead position
+ // (the theory here is that if there are no characters at all after the lookahead
+ // position, that always matches the lookahead criteria)
+ if (c == CharacterIterator.DONE && lookaheadResult == text.getEndIndex()) {
+ result = lookaheadResult;
+ }
+
+ text.setIndex(result);
+ return result;
+ }
+
+ /**
+ * This method backs the iterator back up to a "safe position" in the text.
+ * This is a position that we know, without any context, must be a break position.
+ * The various calling methods then iterate forward from this safe position to
+ * the appropriate position to return. (For more information, see the description
+ * of buildBackwardsStateTable() in RuleBasedBreakIterator.Builder.)
+ */
+ protected int handlePrevious() {
+ CharacterIterator text = getText();
+ int state = START_STATE;
+ int category = 0;
+ int lastCategory = 0;
+ int c = getCurrent();
+
+ // loop until we reach the beginning of the text or transition to state 0
+ while (c != CharacterIterator.DONE && state != STOP_STATE) {
+
+ // save the last character's category and look up the current
+ // character's category
+ lastCategory = category;
+ category = lookupCategory(c);
+
+ // if the current character isn't an ignore character, look up a
+ // state transition in the backwards state table
+ if (category != IGNORE) {
+ state = lookupBackwardState(state, category);
+ }
+
+ // then advance one character backwards
+ c = getPrevious();
+ }
+
+ // if we didn't march off the beginning of the text, we're either one or two
+ // positions away from the real break position. (One because of the call to
+ // previous() at the end of the loop above, and another because the character
+ // that takes us into the stop state will always be the character BEFORE
+ // the break position.)
+ if (c != CharacterIterator.DONE) {
+ if (lastCategory != IGNORE) {
+ getNext();
+ getNext();
+ }
+ else {
+ getNext();
+ }
+ }
+ return text.getIndex();
+ }
+
+ /**
+ * Looks up a character's category (i.e., its category for breaking purposes,
+ * not its Unicode category)
+ */
+ protected int lookupCategory(int c) {
+ if (c < Character.MIN_SUPPLEMENTARY_CODE_POINT) {
+ return charCategoryTable.elementAt((char)c);
+ } else {
+ return supplementaryCharCategoryTable.getValue(c);
+ }
+ }
+
+ /**
+ * Given a current state and a character category, looks up the
+ * next state to transition to in the state table.
+ */
+ protected int lookupState(int state, int category) {
+ return stateTable[state * numCategories + category];
+ }
+
+ /**
+ * Given a current state and a character category, looks up the
+ * next state to transition to in the backwards state table.
+ */
+ protected int lookupBackwardState(int state, int category) {
+ return backwardsStateTable[state * numCategories + category];
+ }
+
+ static long getLong(byte[] buf, int offset) {
+ long num = buf[offset]&0xFF;
+ for (int i = 1; i < 8; i++) {
+ num = num<<8 | (buf[offset+i]&0xFF);
+ }
+ return num;
+ }
+
+ static int getInt(byte[] buf, int offset) {
+ int num = buf[offset]&0xFF;
+ for (int i = 1; i < 4; i++) {
+ num = num<<8 | (buf[offset+i]&0xFF);
+ }
+ return num;
+ }
+
+ static short getShort(byte[] buf, int offset) {
+ short num = (short)(buf[offset]&0xFF);
+ num = (short)(num<<8 | (buf[offset+1]&0xFF));
+ return num;
+ }
+
+ /*
+ * This class exists to work around a bug in incorrect implementations
+ * of CharacterIterator, which incorrectly handle setIndex(endIndex).
+ * This iterator relies only on base.setIndex(n) where n is less than
+ * endIndex.
+ *
+ * One caveat: if the base iterator's begin and end indices change
+ * the change will not be reflected by this wrapper. Does that matter?
+ */
+ // TODO: Review this class to see if it's still required.
+ private static final class SafeCharIterator implements CharacterIterator,
+ Cloneable {
+
+ private CharacterIterator base;
+ private int rangeStart;
+ private int rangeLimit;
+ private int currentIndex;
+
+ SafeCharIterator(CharacterIterator base) {
+ this.base = base;
+ this.rangeStart = base.getBeginIndex();
+ this.rangeLimit = base.getEndIndex();
+ this.currentIndex = base.getIndex();
+ }
+
+ @Override
+ public char first() {
+ return setIndex(rangeStart);
+ }
+
+ @Override
+ public char last() {
+ return setIndex(rangeLimit - 1);
+ }
+
+ @Override
+ public char current() {
+ if (currentIndex < rangeStart || currentIndex >= rangeLimit) {
+ return DONE;
+ }
+ else {
+ return base.setIndex(currentIndex);
+ }
+ }
+
+ @Override
+ public char next() {
+
+ currentIndex++;
+ if (currentIndex >= rangeLimit) {
+ currentIndex = rangeLimit;
+ return DONE;
+ }
+ else {
+ return base.setIndex(currentIndex);
+ }
+ }
+
+ @Override
+ public char previous() {
+
+ currentIndex--;
+ if (currentIndex < rangeStart) {
+ currentIndex = rangeStart;
+ return DONE;
+ }
+ else {
+ return base.setIndex(currentIndex);
+ }
+ }
+
+ @Override
+ public char setIndex(int i) {
+
+ if (i < rangeStart || i > rangeLimit) {
+ throw new IllegalArgumentException("Invalid position");
+ }
+ currentIndex = i;
+ return current();
+ }
+
+ @Override
+ public int getBeginIndex() {
+ return rangeStart;
+ }
+
+ @Override
+ public int getEndIndex() {
+ return rangeLimit;
+ }
+
+ @Override
+ public int getIndex() {
+ return currentIndex;
+ }
+
+ @Override
+ public Object clone() {
+
+ SafeCharIterator copy = null;
+ try {
+ copy = (SafeCharIterator) super.clone();
+ }
+ catch(CloneNotSupportedException e) {
+ throw new Error("Clone not supported: " + e);
+ }
+
+ CharacterIterator copyOfBase = (CharacterIterator) base.clone();
+ copy.base = copyOfBase;
+ return copy;
+ }
+ }
+}