| /* |
| * Copyright 2000-2004 Sun Microsystems, Inc. All Rights Reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| |
| package sun.nio.cs; |
| |
| import java.lang.ref.SoftReference; |
| import java.nio.charset.Charset; |
| import java.nio.charset.spi.CharsetProvider; |
| import java.util.ArrayList; |
| import java.util.TreeMap; |
| import java.util.Iterator; |
| import java.util.Locale; |
| import java.util.Map; |
| import sun.misc.ASCIICaseInsensitiveComparator; |
| |
| |
| /** |
| * Abstract base class for charset providers. |
| * |
| * @author Mark Reinhold |
| */ |
| |
| public class AbstractCharsetProvider |
| extends CharsetProvider |
| { |
| |
| /* Maps canonical names to class names |
| */ |
| private Map classMap |
| = new TreeMap(ASCIICaseInsensitiveComparator.CASE_INSENSITIVE_ORDER); |
| |
| /* Maps alias names to canonical names |
| */ |
| private Map aliasMap |
| = new TreeMap(ASCIICaseInsensitiveComparator.CASE_INSENSITIVE_ORDER); |
| |
| /* Maps canonical names to alias-name arrays |
| */ |
| private Map aliasNameMap |
| = new TreeMap(ASCIICaseInsensitiveComparator.CASE_INSENSITIVE_ORDER); |
| |
| /* Maps canonical names to soft references that hold cached instances |
| */ |
| private Map cache |
| = new TreeMap(ASCIICaseInsensitiveComparator.CASE_INSENSITIVE_ORDER); |
| |
| private String packagePrefix; |
| |
| protected AbstractCharsetProvider() { |
| packagePrefix = "sun.nio.cs"; |
| } |
| |
| protected AbstractCharsetProvider(String pkgPrefixName) { |
| packagePrefix = pkgPrefixName; |
| } |
| |
| /* Add an entry to the given map, but only if no mapping yet exists |
| * for the given name. |
| */ |
| private static void put(Map m, String name, Object value) { |
| if (!m.containsKey(name)) |
| m.put(name, value); |
| } |
| |
| private static void remove(Map m, String name) { |
| Object x = m.remove(name); |
| assert (x != null); |
| } |
| |
| /* Declare support for the given charset |
| */ |
| protected void charset(String name, String className, String[] aliases) { |
| synchronized (this) { |
| put(classMap, name, className); |
| for (int i = 0; i < aliases.length; i++) |
| put(aliasMap, aliases[i], name); |
| put(aliasNameMap, name, aliases); |
| cache.clear(); |
| } |
| } |
| |
| protected void deleteCharset(String name, String[] aliases) { |
| synchronized (this) { |
| remove(classMap, name); |
| for (int i = 0; i < aliases.length; i++) |
| remove(aliasMap, aliases[i]); |
| remove(aliasNameMap, name); |
| cache.clear(); |
| } |
| } |
| |
| /* Late initialization hook, needed by some providers |
| */ |
| protected void init() { } |
| |
| private String canonicalize(String charsetName) { |
| String acn = (String)aliasMap.get(charsetName); |
| return (acn != null) ? acn : charsetName; |
| } |
| |
| private Charset lookup(String csn) { |
| |
| // Check cache first |
| SoftReference sr = (SoftReference)cache.get(csn); |
| if (sr != null) { |
| Charset cs = (Charset)sr.get(); |
| if (cs != null) |
| return cs; |
| } |
| |
| // Do we even support this charset? |
| String cln = (String)classMap.get(csn); |
| |
| if (cln == null) |
| return null; |
| |
| // Instantiate the charset and cache it |
| try { |
| |
| Class c = Class.forName(packagePrefix + "." + cln, |
| true, |
| this.getClass().getClassLoader()); |
| |
| Charset cs = (Charset)c.newInstance(); |
| cache.put(csn, new SoftReference(cs)); |
| return cs; |
| } catch (ClassNotFoundException x) { |
| return null; |
| } catch (IllegalAccessException x) { |
| return null; |
| } catch (InstantiationException x) { |
| return null; |
| } |
| } |
| |
| public final Charset charsetForName(String charsetName) { |
| synchronized (this) { |
| init(); |
| return lookup(canonicalize(charsetName)); |
| } |
| } |
| |
| public final Iterator<Charset> charsets() { |
| |
| final ArrayList ks; |
| synchronized (this) { |
| init(); |
| ks = new ArrayList(classMap.keySet()); |
| } |
| |
| return new Iterator<Charset>() { |
| Iterator i = ks.iterator(); |
| |
| public boolean hasNext() { |
| return i.hasNext(); |
| } |
| |
| public Charset next() { |
| String csn = (String)i.next(); |
| return lookup(csn); |
| } |
| |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| }; |
| } |
| |
| public final String[] aliases(String charsetName) { |
| synchronized (this) { |
| init(); |
| return (String[])aliasNameMap.get(charsetName); |
| } |
| } |
| |
| } |