Initial revision
From-SVN: r102074
This commit is contained in:
Tom Tromey
@@ -0,0 +1,406 @@
|
||||
/* Charset.java --
|
||||
Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
|
||||
|
||||
This file is part of GNU Classpath.
|
||||
|
||||
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., 51 Franklin Street, Fifth Floor, Boston, MA
|
||||
02110-1301 USA.
|
||||
|
||||
Linking this library statically or dynamically with other modules is
|
||||
making a combined work based on this library. Thus, the terms and
|
||||
conditions of the GNU General Public License cover the whole
|
||||
combination.
|
||||
|
||||
As a special exception, the copyright holders of this library give you
|
||||
permission to link this library with independent modules to produce an
|
||||
executable, regardless of the license terms of these independent
|
||||
modules, and to copy and distribute the resulting executable under
|
||||
terms of your choice, provided that you also meet, for each linked
|
||||
independent module, the terms and conditions of the license of that
|
||||
module. An independent module is a module which is not derived from
|
||||
or based on this library. If you modify this library, you may extend
|
||||
this exception to your version of the library, but you are not
|
||||
obligated to do so. If you do not wish to do so, delete this
|
||||
exception statement from your version. */
|
||||
|
||||
|
||||
package java.nio.charset;
|
||||
|
||||
import gnu.classpath.SystemProperties;
|
||||
|
||||
import gnu.java.nio.charset.Provider;
|
||||
import gnu.java.nio.charset.iconv.IconvProvider;
|
||||
|
||||
import java.io.BufferedReader;
|
||||
import java.io.InputStreamReader;
|
||||
import java.net.URL;
|
||||
import java.nio.ByteBuffer;
|
||||
import java.nio.CharBuffer;
|
||||
import java.nio.charset.spi.CharsetProvider;
|
||||
import java.util.Collections;
|
||||
import java.util.Enumeration;
|
||||
import java.util.HashSet;
|
||||
import java.util.Iterator;
|
||||
import java.util.LinkedHashSet;
|
||||
import java.util.Locale;
|
||||
import java.util.Set;
|
||||
import java.util.SortedMap;
|
||||
import java.util.TreeMap;
|
||||
|
||||
/**
|
||||
* @author Jesse Rosenstock
|
||||
* @since 1.4
|
||||
* @status updated to 1.5
|
||||
*/
|
||||
public abstract class Charset implements Comparable
|
||||
{
|
||||
private CharsetEncoder cachedEncoder;
|
||||
private CharsetDecoder cachedDecoder;
|
||||
|
||||
/**
|
||||
* Charset providers.
|
||||
*/
|
||||
private static CharsetProvider[] providers;
|
||||
|
||||
private final String canonicalName;
|
||||
private final String[] aliases;
|
||||
|
||||
protected Charset (String canonicalName, String[] aliases)
|
||||
{
|
||||
checkName (canonicalName);
|
||||
if (aliases != null)
|
||||
{
|
||||
int n = aliases.length;
|
||||
for (int i = 0; i < n; ++i)
|
||||
checkName (aliases[i]);
|
||||
}
|
||||
|
||||
cachedEncoder = null;
|
||||
cachedDecoder = null;
|
||||
this.canonicalName = canonicalName;
|
||||
this.aliases = aliases;
|
||||
}
|
||||
|
||||
/**
|
||||
* @throws IllegalCharsetNameException if the name is illegal
|
||||
*/
|
||||
private static void checkName (String name)
|
||||
{
|
||||
int n = name.length ();
|
||||
|
||||
if (n == 0)
|
||||
throw new IllegalCharsetNameException (name);
|
||||
|
||||
char ch = name.charAt (0);
|
||||
if (!(('A' <= ch && ch <= 'Z')
|
||||
|| ('a' <= ch && ch <= 'z')
|
||||
|| ('0' <= ch && ch <= '9')))
|
||||
throw new IllegalCharsetNameException (name);
|
||||
|
||||
for (int i = 1; i < n; ++i)
|
||||
{
|
||||
ch = name.charAt (i);
|
||||
if (!(('A' <= ch && ch <= 'Z')
|
||||
|| ('a' <= ch && ch <= 'z')
|
||||
|| ('0' <= ch && ch <= '9')
|
||||
|| ch == '-' || ch == '.' || ch == ':' || ch == '_'))
|
||||
throw new IllegalCharsetNameException (name);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the system default charset.
|
||||
*
|
||||
* This may be set by the user or VM with the file.encoding
|
||||
* property.
|
||||
*/
|
||||
public static Charset defaultCharset()
|
||||
{
|
||||
String encoding;
|
||||
|
||||
try
|
||||
{
|
||||
encoding = SystemProperties.getProperty("file.encoding");
|
||||
}
|
||||
catch(SecurityException e)
|
||||
{
|
||||
// Use fallback.
|
||||
encoding = "ISO-8859-1";
|
||||
}
|
||||
catch(IllegalArgumentException e)
|
||||
{
|
||||
// Use fallback.
|
||||
encoding = "ISO-8859-1";
|
||||
}
|
||||
|
||||
try
|
||||
{
|
||||
return forName(encoding);
|
||||
}
|
||||
catch(UnsupportedCharsetException e)
|
||||
{
|
||||
// Ignore.
|
||||
}
|
||||
catch(IllegalCharsetNameException e)
|
||||
{
|
||||
// Ignore.
|
||||
}
|
||||
catch(IllegalArgumentException e)
|
||||
{
|
||||
// Ignore.
|
||||
}
|
||||
|
||||
throw new IllegalStateException("Can't get default charset!");
|
||||
}
|
||||
|
||||
public static boolean isSupported (String charsetName)
|
||||
{
|
||||
return charsetForName (charsetName) != null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the Charset instance for the charset of the given name.
|
||||
*
|
||||
* @param charsetName
|
||||
* @return
|
||||
* @throws UnsupportedCharsetException if this VM does not support
|
||||
* the charset of the given name.
|
||||
* @throws IllegalCharsetNameException if the given charset name is
|
||||
* legal.
|
||||
* @throws IllegalArgumentException if <code>charsetName</code> is null.
|
||||
*/
|
||||
public static Charset forName (String charsetName)
|
||||
{
|
||||
// Throws IllegalArgumentException as the JDK does.
|
||||
if(charsetName == null)
|
||||
throw new IllegalArgumentException("Charset name must not be null.");
|
||||
|
||||
Charset cs = charsetForName (charsetName);
|
||||
if (cs == null)
|
||||
throw new UnsupportedCharsetException (charsetName);
|
||||
return cs;
|
||||
}
|
||||
|
||||
/**
|
||||
* Retrieves a charset for the given charset name.
|
||||
*
|
||||
* @return A charset object for the charset with the specified name, or
|
||||
* <code>null</code> if no such charset exists.
|
||||
*
|
||||
* @throws IllegalCharsetNameException if the name is illegal
|
||||
*/
|
||||
private static Charset charsetForName(String charsetName)
|
||||
{
|
||||
checkName (charsetName);
|
||||
Charset cs = null;
|
||||
CharsetProvider[] providers = providers2();
|
||||
for (int i = 0; i < providers.length; i++)
|
||||
{
|
||||
cs = providers[i].charsetForName(charsetName);
|
||||
if (cs != null)
|
||||
break;
|
||||
}
|
||||
return cs;
|
||||
}
|
||||
|
||||
public static SortedMap availableCharsets()
|
||||
{
|
||||
TreeMap charsets = new TreeMap(String.CASE_INSENSITIVE_ORDER);
|
||||
|
||||
CharsetProvider[] providers = providers2();
|
||||
for (int j = 0; j < providers.length; j++)
|
||||
{
|
||||
for (Iterator i = providers[j].charsets(); i.hasNext(); )
|
||||
{
|
||||
Charset cs = (Charset) i.next();
|
||||
charsets.put(cs.name(), cs);
|
||||
}
|
||||
}
|
||||
|
||||
return Collections.unmodifiableSortedMap(charsets);
|
||||
}
|
||||
|
||||
private static CharsetProvider provider()
|
||||
{
|
||||
String useIconv = SystemProperties.getProperty
|
||||
("gnu.classpath.nio.charset.provider.iconv");
|
||||
|
||||
if (useIconv != null)
|
||||
return IconvProvider.provider();
|
||||
|
||||
return Provider.provider();
|
||||
}
|
||||
|
||||
/**
|
||||
* We need to support multiple providers, reading them from
|
||||
* java.nio.charset.spi.CharsetProvider in the resource directory
|
||||
* META-INF/services.
|
||||
*/
|
||||
private static CharsetProvider[] providers2()
|
||||
{
|
||||
if (providers == null)
|
||||
{
|
||||
try
|
||||
{
|
||||
Enumeration en = ClassLoader.getSystemResources
|
||||
("META-INF/services/java.nio.charset.spi.CharsetProvider");
|
||||
LinkedHashSet set = new LinkedHashSet();
|
||||
set.add(provider());
|
||||
while (en.hasMoreElements())
|
||||
{
|
||||
BufferedReader rdr = new BufferedReader(new InputStreamReader
|
||||
(((URL) (en.nextElement())).openStream()));
|
||||
while (true)
|
||||
{
|
||||
String s = rdr.readLine();
|
||||
if (s == null)
|
||||
break;
|
||||
CharsetProvider p =
|
||||
(CharsetProvider) ((Class.forName(s)).newInstance());
|
||||
set.add(p);
|
||||
}
|
||||
}
|
||||
|
||||
providers = new CharsetProvider[set.size()];
|
||||
set.toArray(providers);
|
||||
}
|
||||
catch (Exception e)
|
||||
{
|
||||
throw new RuntimeException(e);
|
||||
}
|
||||
}
|
||||
return providers;
|
||||
}
|
||||
|
||||
public final String name ()
|
||||
{
|
||||
return canonicalName;
|
||||
}
|
||||
|
||||
public final Set aliases ()
|
||||
{
|
||||
if (aliases == null)
|
||||
return Collections.EMPTY_SET;
|
||||
|
||||
// should we cache the aliasSet instead?
|
||||
int n = aliases.length;
|
||||
HashSet aliasSet = new HashSet (n);
|
||||
for (int i = 0; i < n; ++i)
|
||||
aliasSet.add (aliases[i]);
|
||||
return Collections.unmodifiableSet (aliasSet);
|
||||
}
|
||||
|
||||
public String displayName ()
|
||||
{
|
||||
return canonicalName;
|
||||
}
|
||||
|
||||
public String displayName (Locale locale)
|
||||
{
|
||||
return canonicalName;
|
||||
}
|
||||
|
||||
public final boolean isRegistered ()
|
||||
{
|
||||
return (!canonicalName.startsWith ("x-")
|
||||
&& !canonicalName.startsWith ("X-"));
|
||||
}
|
||||
|
||||
public abstract boolean contains (Charset cs);
|
||||
|
||||
public abstract CharsetDecoder newDecoder ();
|
||||
|
||||
public abstract CharsetEncoder newEncoder ();
|
||||
|
||||
public boolean canEncode ()
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
// NB: This implementation serializes different threads calling
|
||||
// Charset.encode(), a potential performance problem. It might
|
||||
// be better to remove the cache, or use ThreadLocal to cache on
|
||||
// a per-thread basis.
|
||||
public final synchronized ByteBuffer encode (CharBuffer cb)
|
||||
{
|
||||
try
|
||||
{
|
||||
if (cachedEncoder == null)
|
||||
{
|
||||
cachedEncoder = newEncoder ()
|
||||
.onMalformedInput (CodingErrorAction.REPLACE)
|
||||
.onUnmappableCharacter (CodingErrorAction.REPLACE);
|
||||
} else
|
||||
cachedEncoder.reset();
|
||||
return cachedEncoder.encode (cb);
|
||||
}
|
||||
catch (CharacterCodingException e)
|
||||
{
|
||||
throw new AssertionError (e);
|
||||
}
|
||||
}
|
||||
|
||||
public final ByteBuffer encode (String str)
|
||||
{
|
||||
return encode (CharBuffer.wrap (str));
|
||||
}
|
||||
|
||||
// NB: This implementation serializes different threads calling
|
||||
// Charset.decode(), a potential performance problem. It might
|
||||
// be better to remove the cache, or use ThreadLocal to cache on
|
||||
// a per-thread basis.
|
||||
public final synchronized CharBuffer decode (ByteBuffer bb)
|
||||
{
|
||||
try
|
||||
{
|
||||
if (cachedDecoder == null)
|
||||
{
|
||||
cachedDecoder = newDecoder ()
|
||||
.onMalformedInput (CodingErrorAction.REPLACE)
|
||||
.onUnmappableCharacter (CodingErrorAction.REPLACE);
|
||||
} else
|
||||
cachedDecoder.reset();
|
||||
|
||||
return cachedDecoder.decode (bb);
|
||||
}
|
||||
catch (CharacterCodingException e)
|
||||
{
|
||||
throw new AssertionError (e);
|
||||
}
|
||||
}
|
||||
|
||||
public final int compareTo (Object ob)
|
||||
{
|
||||
return canonicalName.compareToIgnoreCase (((Charset) ob).canonicalName);
|
||||
}
|
||||
|
||||
public final int hashCode ()
|
||||
{
|
||||
return canonicalName.hashCode ();
|
||||
}
|
||||
|
||||
public final boolean equals (Object ob)
|
||||
{
|
||||
if (ob instanceof Charset)
|
||||
return canonicalName.equalsIgnoreCase (((Charset) ob).canonicalName);
|
||||
else
|
||||
return false;
|
||||
}
|
||||
|
||||
public final String toString ()
|
||||
{
|
||||
return canonicalName;
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user