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	/*
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	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
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	* published by the Free Software Foundation. Oracle designates this
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	*
	* 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
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	/*
	* (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
	* (C) Copyright IBM Corp. 1996-1998 - 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 java.text;

	import java.text.Normalizer;
	import java.util.Vector;
	import java.util.Locale;

	/**
	* The <code>RuleBasedCollator</code> class is a concrete subclass of
	* <code>Collator</code> that provides a simple, data-driven, table
	* collator. With this class you can create a customized table-based
	* <code>Collator</code>. <code>RuleBasedCollator</code> maps
	* characters to sort keys.
	*
	* <p>
	* <code>RuleBasedCollator</code> has the following restrictions
	* for efficiency (other subclasses may be used for more complex languages) :
	* <ol>
	* <li>If a special collation rule controlled by a <modifier> is
	specified it applies to the whole collator object.
	* <li>All non-mentioned characters are at the end of the
	* collation order.
	* </ol>
	*
	* <p>
	* The collation table is composed of a list of collation rules, where each
	* rule is of one of three forms:
	* <pre>
	* <modifier>
	* <relation> <text-argument>
	* <reset> <text-argument>
	* </pre>
	* The definitions of the rule elements is as follows:
	* <UL>
	* <LI><strong>Text-Argument</strong>: A text-argument is any sequence of
	* characters, excluding special characters (that is, common
	* whitespace characters [0009-000D, 0020] and rule syntax characters
	* [0021-002F, 003A-0040, 005B-0060, 007B-007E]). If those
	* characters are desired, you can put them in single quotes
	* (e.g. ampersand => '&'). Note that unquoted white space characters
	* are ignored; e.g. <code>b c</code> is treated as <code>bc</code>.
	* <LI><strong>Modifier</strong>: There are currently two modifiers that
	* turn on special collation rules.
	* <UL>
	* <LI>'@' : Turns on backwards sorting of accents (secondary
	* differences), as in French.
	* <LI>'!' : Turns on Thai/Lao vowel-consonant swapping. If this
	* rule is in force when a Thai vowel of the range
	* \U0E40-\U0E44 precedes a Thai consonant of the range
	* \U0E01-\U0E2E OR a Lao vowel of the range \U0EC0-\U0EC4
	* precedes a Lao consonant of the range \U0E81-\U0EAE then
	* the vowel is placed after the consonant for collation
	* purposes.
	* </UL>
	* <p>'@' : Indicates that accents are sorted backwards, as in French.
	* <LI><strong>Relation</strong>: The relations are the following:
	* <UL>
	* <LI>'<' : Greater, as a letter difference (primary)
	* <LI>';' : Greater, as an accent difference (secondary)
	* <LI>',' : Greater, as a case difference (tertiary)
	* <LI>'=' : Equal
	* </UL>
	* <LI><strong>Reset</strong>: There is a single reset
	* which is used primarily for contractions and expansions, but which
	* can also be used to add a modification at the end of a set of rules.
	* <p>'&' : Indicates that the next rule follows the position to where
	* the reset text-argument would be sorted.
	* </UL>
	*
	* <p>
	* This sounds more complicated than it is in practice. For example, the
	* following are equivalent ways of expressing the same thing:
	* <blockquote>
	* <pre>
	* a < b < c
	* a < b & b < c
	* a < c & a < b
	* </pre>
	* </blockquote>
	* Notice that the order is important, as the subsequent item goes immediately
	* after the text-argument. The following are not equivalent:
	* <blockquote>
	* <pre>
	* a < b & a < c
	* a < c & a < b
	* </pre>
	* </blockquote>
	* Either the text-argument must already be present in the sequence, or some
	* initial substring of the text-argument must be present. (e.g. "a < b & ae <
	* e" is valid since "a" is present in the sequence before "ae" is reset). In
	* this latter case, "ae" is not entered and treated as a single character;
	* instead, "e" is sorted as if it were expanded to two characters: "a"
	* followed by an "e". This difference appears in natural languages: in
	* traditional Spanish "ch" is treated as though it contracts to a single
	* character (expressed as "c < ch < d"), while in traditional German
	* a-umlaut is treated as though it expanded to two characters
	* (expressed as "a,A < b,B ... &ae;\u00e3&AE;\u00c3").
	* [\u00e3 and \u00c3 are, of course, the escape sequences for a-umlaut.]
	* <p>
	* <strong>Ignorable Characters</strong>
	* <p>
	* For ignorable characters, the first rule must start with a relation (the
	* examples we have used above are really fragments; "a < b" really should be
	* "< a < b"). If, however, the first relation is not "<", then all the all
	* text-arguments up to the first "<" are ignorable. For example, ", - < a < b"
	* makes "-" an ignorable character, as we saw earlier in the word
	* "black-birds". In the samples for different languages, you see that most
	* accents are ignorable.
	*
	* <p><strong>Normalization and Accents</strong>
	* <p>
	* <code>RuleBasedCollator</code> automatically processes its rule table to
	* include both pre-composed and combining-character versions of
	* accented characters. Even if the provided rule string contains only
	* base characters and separate combining accent characters, the pre-composed
	* accented characters matching all canonical combinations of characters from
	* the rule string will be entered in the table.
	* <p>
	* This allows you to use a RuleBasedCollator to compare accented strings
	* even when the collator is set to NO_DECOMPOSITION. There are two caveats,
	* however. First, if the strings to be collated contain combining
	* sequences that may not be in canonical order, you should set the collator to
	* CANONICAL_DECOMPOSITION or FULL_DECOMPOSITION to enable sorting of
	* combining sequences. Second, if the strings contain characters with
	* compatibility decompositions (such as full-width and half-width forms),
	* you must use FULL_DECOMPOSITION, since the rule tables only include
	* canonical mappings.
	*
	* <p><strong>Errors</strong>
	* <p>
	* The following are errors:
	* <UL>
	* <LI>A text-argument contains unquoted punctuation symbols
	* (e.g. "a < b-c < d").
	* <LI>A relation or reset character not followed by a text-argument
	* (e.g. "a < ,b").
	* <LI>A reset where the text-argument (or an initial substring of the
	* text-argument) is not already in the sequence.
	* (e.g. "a < b & e < f")
	* </UL>
	* If you produce one of these errors, a <code>RuleBasedCollator</code> throws
	* a <code>ParseException</code>.
	*
	* <p><strong>Examples</strong>
	* <p>Simple: "< a < b < c < d"
	* <p>Norwegian: "< a, A < b, B < c, C < d, D < e, E < f, F
	* < g, G < h, H < i, I < j, J < k, K < l, L
	* < m, M < n, N < o, O < p, P < q, Q < r, R
	* < s, S < t, T < u, U < v, V < w, W < x, X
	* < y, Y < z, Z
	* < \u00E6, \u00C6
	* < \u00F8, \u00D8
	* < \u00E5 = a\u030A, \u00C5 = A\u030A;
	* aa, AA"
	*
	* <p>
	* To create a <code>RuleBasedCollator</code> object with specialized
	* rules tailored to your needs, you construct the <code>RuleBasedCollator</code>
	* with the rules contained in a <code>String</code> object. For example:
	* <blockquote>
	* <pre>
	* String simple = "< a< b< c< d";
	* RuleBasedCollator mySimple = new RuleBasedCollator(simple);
	* </pre>
	* </blockquote>
	* Or:
	* <blockquote>
	* <pre>
	* String Norwegian = "< a, A < b, B < c, C < d, D < e, E < f, F < g, G < h, H < i, I" +
	* "< j, J < k, K < l, L < m, M < n, N < o, O < p, P < q, Q < r, R" +
	* "< s, S < t, T < u, U < v, V < w, W < x, X < y, Y < z, Z" +
	* "< \u00E6, \u00C6" + // Latin letter ae & AE
	* "< \u00F8, \u00D8" + // Latin letter o & O with stroke
	* "< \u00E5 = a\u030A," + // Latin letter a with ring above
	* " \u00C5 = A\u030A;" + // Latin letter A with ring above
	* " aa, AA";
	* RuleBasedCollator myNorwegian = new RuleBasedCollator(Norwegian);
	* </pre>
	* </blockquote>
	*
	* <p>
	* A new collation rules string can be created by concatenating rules
	* strings. For example, the rules returned by {@link #getRules()} could
	* be concatenated to combine multiple <code>RuleBasedCollator</code>s.
	*
	* <p>
	* The following example demonstrates how to change the order of
	* non-spacing accents,
	* <blockquote>
	* <pre>
	* // old rule
	* String oldRules = "=\u0301;\u0300;\u0302;\u0308" // main accents
	* + ";\u0327;\u0303;\u0304;\u0305" // main accents
	* + ";\u0306;\u0307;\u0309;\u030A" // main accents
	* + ";\u030B;\u030C;\u030D;\u030E" // main accents
	* + ";\u030F;\u0310;\u0311;\u0312" // main accents
	* + "< a , A ; ae, AE ; \u00e6 , \u00c6"
	* + "< b , B < c, C < e, E & C < d, D";
	* // change the order of accent characters
	* String addOn = "& \u0300 ; \u0308 ; \u0302";
	* RuleBasedCollator myCollator = new RuleBasedCollator(oldRules + addOn);
	* </pre>
	* </blockquote>
	*
	* @see Collator
	* @see CollationElementIterator
	* @author Helena Shih, Laura Werner, Richard Gillam
	*/
	public class RuleBasedCollator extends Collator{
	// IMPLEMENTATION NOTES: The implementation of the collation algorithm is
	// divided across three classes: RuleBasedCollator, RBCollationTables, and
	// CollationElementIterator. RuleBasedCollator contains the collator's
	// transient state and includes the code that uses the other classes to
	// implement comparison and sort-key building. RuleBasedCollator also
	// contains the logic to handle French secondary accent sorting.
	// A RuleBasedCollator has two CollationElementIterators. State doesn't
	// need to be preserved in these objects between calls to compare() or
	// getCollationKey(), but the objects persist anyway to avoid wasting extra
	// creation time. compare() and getCollationKey() are synchronized to ensure
	// thread safety with this scheme. The CollationElementIterator is responsible
	// for generating collation elements from strings and returning one element at
	// a time (sometimes there's a one-to-many or many-to-one mapping between
	// characters and collation elements-- this class handles that).
	// CollationElementIterator depends on RBCollationTables, which contains the
	// collator's static state. RBCollationTables contains the actual data
	// tables specifying the collation order of characters for a particular locale
	// or use. It also contains the base logic that CollationElementIterator
	// uses to map from characters to collation elements. A single RBCollationTables
	// object is shared among all RuleBasedCollators for the same locale, and
	// thus by all the CollationElementIterators they create.

	/**
	* RuleBasedCollator constructor. This takes the table rules and builds
	* a collation table out of them. Please see RuleBasedCollator class
	* description for more details on the collation rule syntax.
	* @see java.util.Locale
	* @param rules the collation rules to build the collation table from.
	* @exception ParseException A format exception
	* will be thrown if the build process of the rules fails. For
	* example, build rule "a < ? < d" will cause the constructor to
	* throw the ParseException because the '?' is not quoted.
	*/
	public RuleBasedCollator(String rules) throws ParseException {
	this(rules, Collator.CANONICAL_DECOMPOSITION);
	}

	/**
	* RuleBasedCollator constructor. This takes the table rules and builds
	* a collation table out of them. Please see RuleBasedCollator class
	* description for more details on the collation rule syntax.
	* @see java.util.Locale
	* @param rules the collation rules to build the collation table from.
	* @param decomp the decomposition strength used to build the
	* collation table and to perform comparisons.
	* @exception ParseException A format exception
	* will be thrown if the build process of the rules fails. For
	* example, build rule "a < ? < d" will cause the constructor to
	* throw the ParseException because the '?' is not quoted.
	*/
	RuleBasedCollator(String rules, int decomp) throws ParseException {
	setStrength(Collator.TERTIARY);
	setDecomposition(decomp);
	tables = new RBCollationTables(rules, decomp);
	}

	/**
	* "Copy constructor." Used in clone() for performance.
	*/
	private RuleBasedCollator(RuleBasedCollator that) {
	setStrength(that.getStrength());
	setDecomposition(that.getDecomposition());
	tables = that.tables;
	}

	/**
	* Gets the table-based rules for the collation object.
	* @return returns the collation rules that the table collation object
	* was created from.
	*/
	public String getRules()
	{
	return tables.getRules();
	}

	/**
	* Returns a CollationElementIterator for the given String.
	*
	* @param source the string to be collated
	* @return a {@code CollationElementIterator} object
	* @see java.text.CollationElementIterator
	*/
	public CollationElementIterator getCollationElementIterator(String source) {
	return new CollationElementIterator( source, this );
	}

	/**
	* Returns a CollationElementIterator for the given CharacterIterator.
	*
	* @param source the character iterator to be collated
	* @return a {@code CollationElementIterator} object
	* @see java.text.CollationElementIterator
	* @since 1.2
	*/
	public CollationElementIterator getCollationElementIterator(
	CharacterIterator source) {
	return new CollationElementIterator( source, this );
	}

	/**
	* Compares the character data stored in two different strings based on the
	* collation rules. Returns information about whether a string is less
	* than, greater than or equal to another string in a language.
	* This can be overriden in a subclass.
	*
	* @exception NullPointerException if <code>source</code> or <code>target</code> is null.
	*/
	public synchronized int compare(String source, String target)
	{
	if (source == null \|\| target == null) {
	throw new NullPointerException();
	}

	// The basic algorithm here is that we use CollationElementIterators
	// to step through both the source and target strings. We compare each
	// collation element in the source string against the corresponding one
	// in the target, checking for differences.
	//
	// If a difference is found, we set <result> to LESS or GREATER to
	// indicate whether the source string is less or greater than the target.
	//
	// However, it's not that simple. If we find a tertiary difference
	// (e.g. 'A' vs. 'a') near the beginning of a string, it can be
	// overridden by a primary difference (e.g. "A" vs. "B") later in
	// the string. For example, "AA" < "aB", even though 'A' > 'a'.
	//
	// To keep track of this, we use strengthResult to keep track of the
	// strength of the most significant difference that has been found
	// so far. When we find a difference whose strength is greater than
	// strengthResult, it overrides the last difference (if any) that
	// was found.

	int result = Collator.EQUAL;

	if (sourceCursor == null) {
	sourceCursor = getCollationElementIterator(source);
	} else {
	sourceCursor.setText(source);
	}
	if (targetCursor == null) {
	targetCursor = getCollationElementIterator(target);
	} else {
	targetCursor.setText(target);
	}

	int sOrder = 0, tOrder = 0;

	boolean initialCheckSecTer = getStrength() >= Collator.SECONDARY;
	boolean checkSecTer = initialCheckSecTer;
	boolean checkTertiary = getStrength() >= Collator.TERTIARY;

	boolean gets = true, gett = true;

	while(true) {
	// Get the next collation element in each of the strings, unless
	// we've been requested to skip it.
	if (gets) sOrder = sourceCursor.next(); else gets = true;
	if (gett) tOrder = targetCursor.next(); else gett = true;

	// If we've hit the end of one of the strings, jump out of the loop
	if ((sOrder == CollationElementIterator.NULLORDER)\|\|
	(tOrder == CollationElementIterator.NULLORDER))
	break;

	int pSOrder = CollationElementIterator.primaryOrder(sOrder);
	int pTOrder = CollationElementIterator.primaryOrder(tOrder);

	// If there's no difference at this position, we can skip it
	if (sOrder == tOrder) {
	if (tables.isFrenchSec() && pSOrder != 0) {
	if (!checkSecTer) {
	// in french, a secondary difference more to the right is stronger,
	// so accents have to be checked with each base element
	checkSecTer = initialCheckSecTer;
	// but tertiary differences are less important than the first
	// secondary difference, so checking tertiary remains disabled
	checkTertiary = false;
	}
	}
	continue;
	}

	// Compare primary differences first.
	if ( pSOrder != pTOrder )
	{
	if (sOrder == 0) {
	// The entire source element is ignorable.
	// Skip to the next source element, but don't fetch another target element.
	gett = false;
	continue;
	}
	if (tOrder == 0) {
	gets = false;
	continue;
	}

	// The source and target elements aren't ignorable, but it's still possible
	// for the primary component of one of the elements to be ignorable....

	if (pSOrder == 0) // primary order in source is ignorable
	{
	// The source's primary is ignorable, but the target's isn't. We treat ignorables
	// as a secondary difference, so remember that we found one.
	if (checkSecTer) {
	result = Collator.GREATER; // (strength is SECONDARY)
	checkSecTer = false;
	}
	// Skip to the next source element, but don't fetch another target element.
	gett = false;
	}
	else if (pTOrder == 0)
	{
	// record differences - see the comment above.
	if (checkSecTer) {
	result = Collator.LESS; // (strength is SECONDARY)
	checkSecTer = false;
	}
	// Skip to the next source element, but don't fetch another target element.
	gets = false;
	} else {
	// Neither of the orders is ignorable, and we already know that the primary
	// orders are different because of the (pSOrder != pTOrder) test above.
	// Record the difference and stop the comparison.
	if (pSOrder < pTOrder) {
	return Collator.LESS; // (strength is PRIMARY)
	} else {
	return Collator.GREATER; // (strength is PRIMARY)
	}
	}
	} else { // else of if ( pSOrder != pTOrder )
	// primary order is the same, but complete order is different. So there
	// are no base elements at this point, only ignorables (Since the strings are
	// normalized)

	if (checkSecTer) {
	// a secondary or tertiary difference may still matter
	short secSOrder = CollationElementIterator.secondaryOrder(sOrder);
	short secTOrder = CollationElementIterator.secondaryOrder(tOrder);
	if (secSOrder != secTOrder) {
	// there is a secondary difference
	result = (secSOrder < secTOrder) ? Collator.LESS : Collator.GREATER;
	// (strength is SECONDARY)
	checkSecTer = false;
	// (even in french, only the first secondary difference within
	// a base character matters)
	} else {
	if (checkTertiary) {
	// a tertiary difference may still matter
	short terSOrder = CollationElementIterator.tertiaryOrder(sOrder);
	short terTOrder = CollationElementIterator.tertiaryOrder(tOrder);
	if (terSOrder != terTOrder) {
	// there is a tertiary difference
	result = (terSOrder < terTOrder) ? Collator.LESS : Collator.GREATER;
	// (strength is TERTIARY)
	checkTertiary = false;
	}
	}
	}
	} // if (checkSecTer)

	} // if ( pSOrder != pTOrder )
	} // while()

	if (sOrder != CollationElementIterator.NULLORDER) {
	// (tOrder must be CollationElementIterator::NULLORDER,
	// since this point is only reached when sOrder or tOrder is NULLORDER.)
	// The source string has more elements, but the target string hasn't.
	do {
	if (CollationElementIterator.primaryOrder(sOrder) != 0) {
	// We found an additional non-ignorable base character in the source string.
	// This is a primary difference, so the source is greater
	return Collator.GREATER; // (strength is PRIMARY)
	}
	else if (CollationElementIterator.secondaryOrder(sOrder) != 0) {
	// Additional secondary elements mean the source string is greater
	if (checkSecTer) {
	result = Collator.GREATER; // (strength is SECONDARY)
	checkSecTer = false;
	}
	}
	} while ((sOrder = sourceCursor.next()) != CollationElementIterator.NULLORDER);
	}
	else if (tOrder != CollationElementIterator.NULLORDER) {
	// The target string has more elements, but the source string hasn't.
	do {
	if (CollationElementIterator.primaryOrder(tOrder) != 0)
	// We found an additional non-ignorable base character in the target string.
	// This is a primary difference, so the source is less
	return Collator.LESS; // (strength is PRIMARY)
	else if (CollationElementIterator.secondaryOrder(tOrder) != 0) {
	// Additional secondary elements in the target mean the source string is less
	if (checkSecTer) {
	result = Collator.LESS; // (strength is SECONDARY)
	checkSecTer = false;
	}
	}
	} while ((tOrder = targetCursor.next()) != CollationElementIterator.NULLORDER);
	}

	// For IDENTICAL comparisons, we use a bitwise character comparison
	// as a tiebreaker if all else is equal
	if (result == 0 && getStrength() == IDENTICAL) {
	int mode = getDecomposition();
	Normalizer.Form form;
	if (mode == CANONICAL_DECOMPOSITION) {
	form = Normalizer.Form.NFD;
	} else if (mode == FULL_DECOMPOSITION) {
	form = Normalizer.Form.NFKD;
	} else {
	return source.compareTo(target);
	}

	String sourceDecomposition = Normalizer.normalize(source, form);
	String targetDecomposition = Normalizer.normalize(target, form);
	return sourceDecomposition.compareTo(targetDecomposition);
	}
	return result;
	}

	/**
	* Transforms the string into a series of characters that can be compared
	* with CollationKey.compareTo. This overrides java.text.Collator.getCollationKey.
	* It can be overriden in a subclass.
	*/
	public synchronized CollationKey getCollationKey(String source)
	{
	//
	// The basic algorithm here is to find all of the collation elements for each
	// character in the source string, convert them to a char representation,
	// and put them into the collation key. But it's trickier than that.
	// Each collation element in a string has three components: primary (A vs B),
	// secondary (A vs A-acute), and tertiary (A' vs a); and a primary difference
	// at the end of a string takes precedence over a secondary or tertiary
	// difference earlier in the string.
	//
	// To account for this, we put all of the primary orders at the beginning of the
	// string, followed by the secondary and tertiary orders, separated by nulls.
	//
	// Here's a hypothetical example, with the collation element represented as
	// a three-digit number, one digit for primary, one for secondary, etc.
	//
	// String: A a B \u00e9 <--(e-acute)
	// Collation Elements: 101 100 201 510
	//
	// Collation Key: 1125<null>0001<null>1010
	//
	// To make things even trickier, secondary differences (accent marks) are compared
	// starting at the end of the string in languages with French secondary ordering.
	// But when comparing the accent marks on a single base character, they are compared
	// from the beginning. To handle this, we reverse all of the accents that belong
	// to each base character, then we reverse the entire string of secondary orderings
	// at the end. Taking the same example above, a French collator might return
	// this instead:
	//
	// Collation Key: 1125<null>1000<null>1010
	//
	if (source == null)
	return null;

	if (primResult == null) {
	primResult = new StringBuffer();
	secResult = new StringBuffer();
	terResult = new StringBuffer();
	} else {
	primResult.setLength(0);
	secResult.setLength(0);
	terResult.setLength(0);
	}
	int order = 0;
	boolean compareSec = (getStrength() >= Collator.SECONDARY);
	boolean compareTer = (getStrength() >= Collator.TERTIARY);
	int secOrder = CollationElementIterator.NULLORDER;
	int terOrder = CollationElementIterator.NULLORDER;
	int preSecIgnore = 0;

	if (sourceCursor == null) {
	sourceCursor = getCollationElementIterator(source);
	} else {
	sourceCursor.setText(source);
	}

	// walk through each character
	while ((order = sourceCursor.next()) !=
	CollationElementIterator.NULLORDER)
	{
	secOrder = CollationElementIterator.secondaryOrder(order);
	terOrder = CollationElementIterator.tertiaryOrder(order);
	if (!CollationElementIterator.isIgnorable(order))
	{
	primResult.append((char) (CollationElementIterator.primaryOrder(order)
	+ COLLATIONKEYOFFSET));

	if (compareSec) {
	//
	// accumulate all of the ignorable/secondary characters attached
	// to a given base character
	//
	if (tables.isFrenchSec() && preSecIgnore < secResult.length()) {
	//
	// We're doing reversed secondary ordering and we've hit a base
	// (non-ignorable) character. Reverse any secondary orderings
	// that applied to the last base character. (see block comment above.)
	//
	RBCollationTables.reverse(secResult, preSecIgnore, secResult.length());
	}
	// Remember where we are in the secondary orderings - this is how far
	// back to go if we need to reverse them later.
	secResult.append((char)(secOrder+ COLLATIONKEYOFFSET));
	preSecIgnore = secResult.length();
	}
	if (compareTer) {
	terResult.append((char)(terOrder+ COLLATIONKEYOFFSET));
	}
	}
	else
	{
	if (compareSec && secOrder != 0)
	secResult.append((char)
	(secOrder + tables.getMaxSecOrder() + COLLATIONKEYOFFSET));
	if (compareTer && terOrder != 0)
	terResult.append((char)
	(terOrder + tables.getMaxTerOrder() + COLLATIONKEYOFFSET));
	}
	}
	if (tables.isFrenchSec())
	{
	if (preSecIgnore < secResult.length()) {
	// If we've accumulated any secondary characters after the last base character,
	// reverse them.
	RBCollationTables.reverse(secResult, preSecIgnore, secResult.length());
	}
	// And now reverse the entire secResult to get French secondary ordering.
	RBCollationTables.reverse(secResult, 0, secResult.length());
	}
	primResult.append((char)0);
	secResult.append((char)0);
	secResult.append(terResult.toString());
	primResult.append(secResult.toString());

	if (getStrength() == IDENTICAL) {
	primResult.append((char)0);
	int mode = getDecomposition();
	if (mode == CANONICAL_DECOMPOSITION) {
	primResult.append(Normalizer.normalize(source, Normalizer.Form.NFD));
	} else if (mode == FULL_DECOMPOSITION) {
	primResult.append(Normalizer.normalize(source, Normalizer.Form.NFKD));
	} else {
	primResult.append(source);
	}
	}
	return new RuleBasedCollationKey(source, primResult.toString());
	}

	/**
	* Standard override; no change in semantics.
	*/
	public Object clone() {
	// if we know we're not actually a subclass of RuleBasedCollator
	// (this class really should have been made final), bypass
	// Object.clone() and use our "copy constructor". This is faster.
	if (getClass() == RuleBasedCollator.class) {
	return new RuleBasedCollator(this);
	}
	else {
	RuleBasedCollator result = (RuleBasedCollator) super.clone();
	result.primResult = null;
	result.secResult = null;
	result.terResult = null;
	result.sourceCursor = null;
	result.targetCursor = null;
	return result;
	}
	}

	/**
	* Compares the equality of two collation objects.
	* @param obj the table-based collation object to be compared with this.
	* @return true if the current table-based collation object is the same
	* as the table-based collation object obj; false otherwise.
	*/
	public boolean equals(Object obj) {
	if (obj == null) return false;
	if (!super.equals(obj)) return false; // super does class check
	RuleBasedCollator other = (RuleBasedCollator) obj;
	// all other non-transient information is also contained in rules.
	return (getRules().equals(other.getRules()));
	}

	/**
	* Generates the hash code for the table-based collation object
	*/
	public int hashCode() {
	return getRules().hashCode();
	}

	/**
	* Allows CollationElementIterator access to the tables object
	*/
	RBCollationTables getTables() {
	return tables;
	}

	// ==============================================================
	// private
	// ==============================================================

	final static int CHARINDEX = 0x70000000; // need look up in .commit()
	final static int EXPANDCHARINDEX = 0x7E000000; // Expand index follows
	final static int CONTRACTCHARINDEX = 0x7F000000; // contract indexes follow
	final static int UNMAPPED = 0xFFFFFFFF;

	private final static int COLLATIONKEYOFFSET = 1;

	private RBCollationTables tables = null;

	// Internal objects that are cached across calls so that they don't have to
	// be created/destroyed on every call to compare() and getCollationKey()
	private StringBuffer primResult = null;
	private StringBuffer secResult = null;
	private StringBuffer terResult = null;
	private CollationElementIterator sourceCursor = null;
	private CollationElementIterator targetCursor = null;
	}

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