Source for gnu.java.nio.charset.iconv.IconvProvider

   1: /* IconvProvider.java --
   2:    Copyright (C) 2005 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.nio.charset.iconv;
  40: 
  41: import java.nio.charset.Charset;
  42: import java.nio.charset.spi.CharsetProvider;
  43: import java.util.Collections;
  44: import java.util.HashMap;
  45: import java.util.Iterator;
  46: import java.util.Vector;
  47: 
  48: /**
  49:  * Charset provider wrapping iconv.
  50:  *
  51:  * @author Sven de Marothy
  52:  */
  53: public final class IconvProvider extends CharsetProvider
  54: {
  55:   private static IconvProvider singleton;
  56: 
  57:   static
  58:     {
  59:       synchronized (IconvProvider.class)
  60:         {
  61:       singleton = null;
  62:         }
  63:     }
  64: 
  65:   // Declaring the construtor public may violate the use of singleton.
  66:   // But it must be public so that an instance of this class can be
  67:   // created by Class.newInstance(), which is the case when this provider is
  68:   // defined in META-INF/services/java.nio.charset.spi.CharsetProvider.
  69:   public IconvProvider()
  70:   {
  71:     IconvMetaData.setup();
  72:   }
  73: 
  74:   public Iterator charsets()
  75:   {
  76:     Vector names = IconvMetaData.charsets();
  77:     Vector charsets = new Vector();
  78:     for (int i = 0; i < names.size(); i++)
  79:       {
  80:     try
  81:       {
  82:         charsets.add(new IconvCharset((IconvMetaData) names.elementAt(i)));
  83:       }
  84:     catch (IllegalArgumentException e)
  85:       {
  86:       }
  87:       }
  88:     return charsets.iterator();
  89:   }
  90: 
  91:   public Charset charsetForName(String charsetName)
  92:   {
  93:     try
  94:       {
  95:     IconvMetaData info = IconvMetaData.get(charsetName);
  96: 
  97:     // Try anyway if the set isn't found.
  98:     if (info == null)
  99:       info = new IconvMetaData(charsetName, 2.0f, 2.0f, 2.0f, 2.0f,
 100:                                new String[] {  }, charsetName);
 101:     return new IconvCharset(info);
 102:       }
 103:     catch (IllegalArgumentException e)
 104:       {
 105:     return null;
 106:       }
 107:   }
 108: 
 109:   public static synchronized IconvProvider provider()
 110:   {
 111:     if (singleton == null)
 112:       singleton = new IconvProvider();
 113:     return singleton;
 114:   }
 115: }