diff options
Diffstat (limited to 'libjava/java/text/Collator.java')
| -rw-r--r-- | libjava/java/text/Collator.java | 277 |
1 files changed, 260 insertions, 17 deletions
diff --git a/libjava/java/text/Collator.java b/libjava/java/text/Collator.java index 9a356c16541..51a053dcf18 100644 --- a/libjava/java/text/Collator.java +++ b/libjava/java/text/Collator.java @@ -1,12 +1,29 @@ -// Collator.java - Locale-sensitive string comparison. +/* Collator.java -- Perform locale dependent String comparisons. + Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. -/* Copyright (C) 1999, 2000 Free Software Foundation +This file is part of GNU Classpath. - This file is part of libgcj. +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +02111-1307 USA. + +As a special exception, if you link this library with other files to +produce an executable, this library does not by itself cause the +resulting executable to be covered by the GNU General Public License. +This exception does not however invalidate any other reasons why the +executable file might be covered by the GNU General Public License. */ -This software is copyrighted work licensed under the terms of the -Libgcj License. Please consult the file "LIBGCJ_LICENSE" for -details. */ package java.text; @@ -16,38 +33,157 @@ import java.util.ResourceBundle; import java.util.Comparator; /** + * This class is the abstract superclass of classes which perform + * locale dependent <code>String</code> comparisons. A caller requests + * an instance of <code>Collator</code> for a particular locale using + * the <code>getInstance()</code> static method in this class. That method + * will return a locale specific subclass of <code>Collator</code> which + * can be used to perform <code>String</code> comparisons for that locale. + * If a subclass of <code>Collator</code> cannot be located for a particular + * locale, a default instance for the current locale will be returned. + * + * In addition to setting the correct locale, there are two additional + * settings that can be adjusted to affect <code>String</code> comparisons: + * strength and decomposition. The strength value determines the level + * of signficance of character differences required for them to sort + * differently. (For example, whether or not capital letters are considered + * different from lower case letters). The decomposition value affects how + * variants of the same character are treated for sorting purposes. (For + * example, whether or not an accent is signficant or not). These settings + * are described in detail in the documentation for the methods and values + * that are related to them. + * * @author Tom Tromey <tromey@cygnus.com> + * @author Aaron M. Renn (arenn@urbanophile.com) * @date March 18, 1999 */ /* Written using "Java Class Libraries", 2nd edition, plus online * API docs for JDK 1.2 from http://www.javasoft.com. * Status: Mostly complete, but parts stubbed out. Look for FIXME. */ - public abstract class Collator implements Comparator, Cloneable { - public static final int NO_DECOMPOSITION = 0; - public static final int CANONICAL_DECOMPOSITION = 1; - public static final int FULL_DECOMPOSITION = 2; - + /** + * This constant is a strength value which indicates that only primary + * differences between characters will be considered signficant. As an + * example, two completely different English letters such as 'a' and 'b' + * are considered to have a primary difference. + */ public static final int PRIMARY = 0; + + /** + * This constant is a strength value which indicates that only secondary + * or primary differences between characters will be considered + * significant. An example of a secondary difference between characters + * are instances of the same letter with different accented forms. + */ public static final int SECONDARY = 1; + + /** + * This constant is a strength value which indicates that tertiary, + * secondary, and primary differences will be considered during sorting. + * An example of a tertiary difference is capitalization of a given letter. + * This is the default value for the strength setting. + */ public static final int TERTIARY = 2; + + /** + * This constant is a strength value which indicates that any difference + * at all between character values are considered significant. + */ public static final int IDENTICAL = 3; + + /** + * This constant indicates that accented characters won't be decomposed + * when performing comparisons. This will yield the fastest results, but + * will only work correctly in call cases for languages which do not + * use accents such as English. + */ + public static final int NO_DECOMPOSITION = 0; + + /** + * This constant indicates that only characters which are canonical variants + * in Unicode 2.0 will be decomposed prior to performing comparisons. This + * will cause accented languages to be sorted correctly. This is the + * default decomposition value. + */ + public static final int CANONICAL_DECOMPOSITION = 1; + + /** + * This constant indicates that both canonical variants and compatibility + * variants in Unicode 2.0 will be decomposed prior to performing + * comparisons. This is the slowest mode, but is required to get the + * correct sorting for certain languages with certain special formats. + */ + public static final int FULL_DECOMPOSITION = 2; + /** + * This method initializes a new instance of <code>Collator</code> to have + * the default strength (TERTIARY) and decomposition + * (CANONICAL_DECOMPOSITION) settings. This constructor is protected and + * is for use by subclasses only. Non-subclass callers should use the + * static <code>getInstance()</code> methods of this class to instantiate + * <code>Collation</code> objects for the desired locale. + */ protected Collator () { strength = TERTIARY; decmp = CANONICAL_DECOMPOSITION; } + /** + * This method compares the two <code>String</code>'s and returns an + * integer indicating whether or not the first argument is less than, + * equal to, or greater than the second argument. The comparison is + * performed according to the rules of the locale for this + * <code>Collator</code> and the strength and decomposition rules in + * effect. + * + * @param str1 The first object to compare + * @param str2 The second object to compare + * + * @return A negative integer if str1 < str2, 0 if str1 == str2, or + * a positive integer if str1 > str2. + */ public abstract int compare (String source, String target); + /** + * This method compares the two <code>Object</code>'s and returns an + * integer indicating whether or not the first argument is less than, + * equal to, or greater than the second argument. These two objects + * must be <code>String</code>'s or an exception will be thrown. + * + * @param obj1 The first object to compare + * @param obj2 The second object to compare + * + * @return A negative integer if obj1 < obj2, 0 if obj1 == obj2, or + * a positive integer if obj1 > obj2. + * + * @exception ClassCastException If the arguments are not instances + * of <code>String</code>. + */ public int compare (Object o1, Object o2) { return compare ((String) o1, (String) o2); } + /** + * This method tests the specified object for equality against this + * object. This will be true if and only if the following conditions are + * met: + * <ul> + * <li>The specified object is not <code>null</code>. + * <li>The specified object is an instance of <code>Collator</code>. + * <li>The specified object has the same strength and decomposition + * settings as this object. + * </ul> + * + * @param obj The <code>Object</code> to test for equality against + * this object. + * + * @return <code>true</code> if the specified object is equal to + * this one, <code>false</code> otherwise. + */ public boolean equals (Object obj) { if (! (obj instanceof Collator)) @@ -56,42 +192,108 @@ public abstract class Collator implements Comparator, Cloneable return decmp == c.decmp && strength == c.strength; } + /** + * This method tests whether the specified <code>String</code>'s are equal + * according to the collation rules for the locale of this object and + * the current strength and decomposition settings. + * + * @param str1 The first <code>String</code> to compare + * @param str2 The second <code>String</code> to compare + * + * @return <code>true</code> if the two strings are equal, + * <code>false</code> otherwise. + */ public boolean equals (String source, String target) { return compare (source, target) == 0; } + /** + * This method returns a copy of this <code>Collator</code> object. + * + * @return A duplicate of this object. + */ public Object clone () { - return super.clone (); + try + { + return super.clone (); + } + catch (CloneNotSupportedException _) + { + return null; + } } + /** + * This method returns an array of <code>Locale</code> objects which is + * the list of locales for which <code>Collator</code> objects exist. + * + * @return The list of locales for which <code>Collator</code>'s exist. + */ public static synchronized Locale[] getAvailableLocales () { - // FIXME. - return null; + // FIXME + Locale[] l = new Locale[1]; + l[0] = Locale.US; + return l; } + /** + * This method transforms the specified <code>String</code> into a + * <code>CollationKey</code> for faster comparisons. This is useful when + * comparisons against a string might be performed multiple times, such + * as during a sort operation. + * + * @param str The <code>String</code> to convert. + * + * @return A <code>CollationKey</code> for the specified <code>String</code>. + */ public abstract CollationKey getCollationKey (String source); + /** + * This method returns the current decomposition setting for this + * object. This * will be one of NO_DECOMPOSITION, + * CANONICAL_DECOMPOSITION, or * FULL_DECOMPOSITION. See the + * documentation for those constants for an * explanation of this + * setting. + * + * @return The current decomposition setting. + */ public synchronized int getDecomposition () { return decmp; } + /** + * This method returns an instance of <code>Collator</code> for the + * default locale. + * + * @return A <code>Collator</code> for the default locale. + */ public static Collator getInstance () { return getInstance (Locale.getDefault()); } + /** + * This method returns an instance of <code>Collator</code> for the + * specified locale. If no <code>Collator</code> exists for the desired + * locale, a <code>Collator</code> for the default locale will be returned. + * + * @param locale The desired localed to load a <code>Collator</code> for. + * + * @return A <code>Collator</code> for the requested locale + */ public static Collator getInstance (Locale loc) { ResourceBundle res; String pattern; try { - res = ResourceBundle.getBundle("gnu.gcj.text.LocaleData", loc); - pattern = res.getString("collatorRule"); + res = ResourceBundle.getBundle("gnu.java.locale.LocaleInformation", + loc); + pattern = res.getString("collation_rules"); } catch (MissingResourceException x) { @@ -107,13 +309,37 @@ public abstract class Collator implements Comparator, Cloneable } } + /** + * This method returns the current strength setting for this object. This + * will be one of PRIMARY, SECONDARY, TERTIARY, or IDENTICAL. See the + * documentation for those constants for an explanation of this setting. + * + * @return The current strength setting. + */ public synchronized int getStrength () { return strength; } + /** + * This method returns a hash code value for this object. + * + * @return A hash value for this object. + */ public abstract int hashCode (); + /** + * This method sets the decomposition setting for this object to the + * specified value. This must be one of NO_DECOMPOSITION, + * CANONICAL_DECOMPOSITION, or FULL_DECOMPOSITION. Otherwise an + * exception will be thrown. See the documentation for those + * contants for an explanation of this setting. + * + * @param decmp The new decomposition setting. + * + * @exception IllegalArgumentException If the requested + * decomposition setting is not valid. + */ public synchronized void setDecomposition (int mode) { if (mode != NO_DECOMPOSITION @@ -123,6 +349,17 @@ public abstract class Collator implements Comparator, Cloneable decmp = mode; } + /** + * This method sets the strength setting for this object to the specified + * value. This must be one of PRIMARY, SECONDARY, TERTIARY, or IDENTICAL. + * Otherwise an exception is thrown. See the documentation for these + * constants for an explanation of this setting. + * + * @param strength The new strength setting. + * + * @exception IllegalArgumentException If the requested strength + * setting value is not valid. + */ public synchronized void setStrength (int strength) { if (strength != PRIMARY && strength != SECONDARY @@ -134,7 +371,13 @@ public abstract class Collator implements Comparator, Cloneable // Decompose a single character and append results to the buffer. native final void decomposeCharacter (char c, StringBuffer buf); - // These names are fixed by the serialization spec. + /** + * This is the current collation decomposition setting. + */ int decmp; + + /** + * This is the current collation strength setting. + */ int strength; } |