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

   1: /* IconvProvider.java --
   2:    Copyright (C) 2005, 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.nio.charset.iconv;
  40: 
  41: import java.nio.charset.Charset;
  42: import java.nio.charset.spi.CharsetProvider;
  43: import java.util.Iterator;
  44: import java.util.Vector;
  45: 
  46: /**
  47:  * Charset provider wrapping iconv.
  48:  *
  49:  * Note: This class is a privileged class, because it can be instantiated without
  50:  * requiring the RuntimePermission("charsetProvider"). There is a check in
  51:  * java.nio.charset.spi.CharsetProvider to skip the security check if the provider
  52:  * is an instance of this class.
  53:  *
  54:  * @author Sven de Marothy
  55:  */
  56: public final class IconvProvider extends CharsetProvider
  57: {
  58:   private static IconvProvider singleton;
  59: 
  60:   // Declaring the construtor public may violate the use of singleton.
  61:   // But it must be public so that an instance of this class can be
  62:   // created by Class.newInstance(), which is the case when this provider is
  63:   // defined in META-INF/services/java.nio.charset.spi.CharsetProvider.
  64:   public IconvProvider()
  65:   {
  66:     IconvMetaData.setup();
  67:   }
  68: 
  69:   public Iterator charsets()
  70:   {
  71:     Vector names = IconvMetaData.charsets();
  72:     Vector charsets = new Vector();
  73:     for (int i = 0; i < names.size(); i++)
  74:       {
  75:         try
  76:           {
  77:             charsets.add(new IconvCharset((IconvMetaData) names.elementAt(i)));
  78:           }
  79:         catch (IllegalArgumentException e)
  80:           {
  81:           }
  82:       }
  83:     return charsets.iterator();
  84:   }
  85: 
  86:   public Charset charsetForName(String charsetName)
  87:   {
  88:     try
  89:       {
  90:         IconvMetaData info = IconvMetaData.get(charsetName);
  91: 
  92:         // Try anyway if the set isn't found.
  93:         if (info == null)
  94:           info = new IconvMetaData(charsetName, 2.0f, 2.0f, 2.0f, 2.0f,
  95:                                    new String[] {  }, charsetName);
  96:         return new IconvCharset(info);
  97:       }
  98:     catch (IllegalArgumentException e)
  99:       {
 100:         return null;
 101:       }
 102:   }
 103: 
 104:   public static synchronized IconvProvider provider()
 105:   {
 106:     if (singleton == null)
 107:       singleton = new IconvProvider();
 108:     return singleton;
 109:   }
 110: }