MS950_HKSCS.java

/*
 * Copyright (c) 2002, 2004, Oracle and/or its affiliates. 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.nio.cs.ext;

import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CharsetEncoder;
import sun.nio.cs.HistoricallyNamedCharset;

public class MS950_HKSCS extends Charset implements HistoricallyNamedCharset
{
    public MS950_HKSCS() {
	super("x-MS950-HKSCS", ExtendedCharsets.aliasesFor("x-MS950-HKSCS"));
    }

    public String historicalName() {
	return "MS950_HKSCS";
    }

    public boolean contains(Charset cs) {
	return ((cs.name().equals("US-ASCII"))
		|| (cs instanceof MS950)
		|| (cs instanceof MS950_HKSCS));
    }

    public CharsetDecoder newDecoder() {
	return new Decoder(this);
    }

    public CharsetEncoder newEncoder() {
	return new Encoder(this);
    }

    private static class Decoder extends HKSCS.Decoder {

	private MS950.Decoder ms950Dec;


	/*
	 * Note current decoder decodes 0x8BC2 --> U+F53A
	 * ie. maps to Unicode PUA.
	 * Unaccounted discrepancy between this mapping
	 * inferred from MS950/windows-950 and the published
	 * MS HKSCS mappings which maps 0x8BC2 --> U+5C22
	 * a character defined with the Unified CJK block
	 */

	protected char decodeDouble(int byte1, int byte2) {
	    char c = super.decodeDouble(byte1, byte2);
	    return (c != REPLACE_CHAR) ? c : ms950Dec.decodeDouble(byte1, byte2);
	}

	private Decoder(Charset cs) {
	    super(cs);
	    ms950Dec = new MS950.Decoder(cs);
	}
    }

    private static class Encoder extends HKSCS.Encoder {

	private MS950.Encoder ms950Enc;

	/*
	 * Note current encoder encodes U+F53A --> 0x8BC2
	 * Published MS HKSCS mappings show
	 * U+5C22 <--> 0x8BC2
	 */
	protected int encodeDouble(char ch) {
	    int r = super.encodeDouble(ch);
	    return (r != 0) ? r : ms950Enc.encodeDouble(ch);
	}

	private Encoder(Charset cs) {
	    super(cs);
	    ms950Enc = new MS950.Encoder(cs);
	}
    }
}