libjava/java/text/BreakIterator.java

   1 // BreakIterator.java - Iterate over logical breaks in text.
   2
   3 /* Copyright (C) 1999  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 package java.text;
  12
  13 import java.io.Serializable;
  14 import java.util.Locale;
  15 import java.util.MissingResourceException;
  16 import java.util.ResourceBundle;
  17
  18 /**
  19  * @author Tom Tromey <tromey@cygnus.com>
  20  * @date March 19, 1999
  21  */
  22 /* Written using "Java Class Libraries", 2nd edition, plus online
  23  * API docs for JDK 1.2 beta from http://www.javasoft.com.
  24  * Status:  Believed complete and correct to 1.1.
  25  */
  26
  27 public abstract class BreakIterator implements Cloneable, Serializable
  28 {
  29   // The value was discovered by writing a test program.
  30   public static final int DONE = -1;
  31
  32   protected BreakIterator ()
  33   {
  34   }
  35
  36   public abstract int current ();
  37   public abstract int first ();
  38   public abstract int following (int pos);
  39
  40   public static synchronized Locale[] getAvailableLocales ()
  41   {
  42     // FIXME.
  43     return null;
  44   }
  45
  46   private static BreakIterator getInstance (String type, Locale loc)
  47   {
  48     String className;
  49     try
  50       {
  51         ResourceBundle res
  52           = ResourceBundle.getBundle("gnu.gcj.text.LocaleData", loc);
  53         className = res.getString(type);
  54       }
  55     catch (MissingResourceException x)
  56       {
  57         return null;
  58       }
  59     try
  60       {
  61         Class k = Class.forName(className);
  62         return (BreakIterator) k.newInstance();
  63       }
  64     catch (ClassNotFoundException x1)
  65       {
  66         return null;
  67       }
  68     catch (InstantiationException x2)
  69       {
  70         return null;
  71       }
  72     catch (IllegalAccessException x3)
  73       {
  74         return null;
  75       }
  76   }
  77
  78   public static BreakIterator getCharacterInstance ()
  79   {
  80     return getCharacterInstance (Locale.getDefault());
  81   }
  82
  83   public static BreakIterator getCharacterInstance (Locale loc)
  84   {
  85     BreakIterator r = getInstance ("CharacterIterator", loc);
  86     if (r == null)
  87       r = new gnu.gcj.text.CharacterBreakIterator ();
  88     return r;
  89   }
  90
  91   public static BreakIterator getLineInstance ()
  92   {
  93     return getLineInstance (Locale.getDefault());
  94   }
  95
  96   public static BreakIterator getLineInstance (Locale loc)
  97   {
  98     BreakIterator r = getInstance ("LineIterator", loc);
  99     if (r == null)
 100       r = new gnu.gcj.text.LineBreakIterator ();
 101     return r;
 102   }
 103
 104   public static BreakIterator getSentenceInstance ()
 105   {
 106     return getSentenceInstance (Locale.getDefault());
 107   }
 108
 109   public static BreakIterator getSentenceInstance (Locale loc)
 110   {
 111     BreakIterator r = getInstance ("SentenceIterator", loc);
 112     if (r == null)
 113       r = new gnu.gcj.text.SentenceBreakIterator ();
 114     return r;
 115   }
 116
 117   public abstract CharacterIterator getText ();
 118
 119   public static BreakIterator getWordInstance ()
 120   {
 121     return getWordInstance (Locale.getDefault());
 122   }
 123
 124   public static BreakIterator getWordInstance (Locale loc)
 125   {
 126     BreakIterator r = getInstance ("WordIterator", loc);
 127     if (r == null)
 128       r = new gnu.gcj.text.WordBreakIterator ();
 129     return r;
 130   }
 131
 132   public boolean isBoundary (int pos)
 133   {
 134     if (pos == 0)
 135       return true;
 136     return following (pos - 1) == pos;
 137   }
 138
 139   public abstract int last ();
 140   public abstract int next ();
 141   public abstract int next (int n);
 142
 143   public int preceding (int pos)
 144   {
 145     if (following (pos) == DONE)
 146       last ();
 147     while (previous () >= pos)
 148       ;
 149     return current ();
 150   }
 151
 152   public abstract int previous ();
 153
 154   public void setText (String newText)
 155   {
 156     setText (new StringCharacterIterator (newText));
 157   }
 158
 159   public abstract void setText (CharacterIterator newText);
 160 }