libjava/classpath/gnu/java/util/regex/RETokenChar.java

   1 /* gnu/regexp/RETokenChar.java
   2    Copyright (C) 2006 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package gnu.java.util.regex;
  40
  41 import gnu.java.lang.CPStringBuilder;
  42
  43 final class RETokenChar extends REToken
  44 {
  45   private char[] ch;
  46   private boolean insens;
  47
  48     RETokenChar (int subIndex, char c, boolean ins)
  49   {
  50     super (subIndex);
  51     insens = ins;
  52     ch = new char[1];
  53       ch[0] = c;
  54   }
  55
  56   int getMinimumLength ()
  57   {
  58     return ch.length;
  59   }
  60
  61   int getMaximumLength ()
  62   {
  63     return ch.length;
  64   }
  65
  66   REMatch matchThis (CharIndexed input, REMatch mymatch)
  67   {
  68     if (matchOneString (input, mymatch.index))
  69       {
  70         mymatch.index += matchedLength;
  71         return mymatch;
  72       }
  73     // java.util.regex.Matcher#hitEnd() requires that the length of
  74     // partial match be counted.
  75     mymatch.index += matchedLength;
  76     input.setHitEnd (mymatch);
  77     return null;
  78   }
  79
  80   private int matchedLength;
  81   private boolean matchOneString (CharIndexed input, int index)
  82   {
  83     matchedLength = 0;
  84     int z = ch.length;
  85     char c;
  86     for (int i = 0; i < z; i++)
  87       {
  88         c = input.charAt (index + i);
  89         if (!charEquals (c, ch[i]))
  90           {
  91             return false;
  92           }
  93         ++matchedLength;
  94       }
  95     return true;
  96   }
  97
  98   private boolean charEquals (char c1, char c2)
  99   {
 100     if (c1 == c2)
 101       return true;
 102     if (!insens)
 103       return false;
 104     if (toLowerCase (c1, unicodeAware) == c2)
 105       return true;
 106     if (toUpperCase (c1, unicodeAware) == c2)
 107       return true;
 108     return false;
 109   }
 110
 111   boolean returnsFixedLengthMatches ()
 112   {
 113     return true;
 114   }
 115
 116   int findFixedLengthMatches (CharIndexed input, REMatch mymatch, int max)
 117   {
 118     int index = mymatch.index;
 119     int numRepeats = 0;
 120     int z = ch.length;
 121     while (true)
 122       {
 123         if (numRepeats >= max)
 124           break;
 125         if (matchOneString (input, index))
 126           {
 127             index += z;
 128             numRepeats++;
 129           }
 130         else
 131           break;
 132       }
 133     return numRepeats;
 134   }
 135
 136   // Overrides REToken.chain() to optimize for strings
 137   boolean chain (REToken next)
 138   {
 139     if (next instanceof RETokenChar && ((RETokenChar) next).insens == insens)
 140       {
 141         RETokenChar cnext = (RETokenChar) next;
 142         int newsize = ch.length + cnext.ch.length;
 143
 144         char[] chTemp = new char[newsize];
 145
 146         System.arraycopy (ch, 0, chTemp, 0, ch.length);
 147         System.arraycopy (cnext.ch, 0, chTemp, ch.length, cnext.ch.length);
 148
 149         ch = chTemp;
 150         if (cnext.next == null)
 151           return false;
 152         return chain (cnext.next);
 153       }
 154     else
 155       return super.chain (next);
 156   }
 157
 158   void dump (CPStringBuilder os)
 159   {
 160     os.append (ch);
 161   }
 162 }