Java example source code file (X11CNS11643.java)

This example Java source code file (X11CNS11643.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

bytebuffer, charbuffer, charsetdecoder, charsetencoder, coderresult, cs1, decoder, encoder, illegalargumentexception, nio, only, string, x11cns11643

The X11CNS11643.java Java example source code

/*
 * Copyright (c) 2001, 2008, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.awt.motif;

import java.nio.CharBuffer;
import java.nio.ByteBuffer;
import java.nio.charset.*;
import sun.nio.cs.ext.EUC_TW;

public abstract class X11CNS11643 extends Charset {
    private final int plane;
    public X11CNS11643 (int plane, String name) {
        super(name, null);
        switch (plane) {
        case 1:
            this.plane = 0; // CS1
            break;
        case 2:
        case 3:
            this.plane = plane;
            break;
        default:
            throw new IllegalArgumentException
                ("Only planes 1, 2, and 3 supported");
        }
    }

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

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

    public boolean contains(Charset cs) {
        return cs instanceof X11CNS11643;
    }

    private class Encoder extends EUC_TW.Encoder {
        private int plane;
        public Encoder(Charset cs, int plane) {
            super(cs);
            this.plane = plane;
        }

        private byte[] bb = new byte[4];
        public boolean canEncode(char c) {
            if (c <= 0x7F) {
                return false;
            }
            int nb = toEUC(c, bb);
            if (nb == -1)
                return false;
            int p = 0;
            if (nb == 4)
                p = (bb[1] & 0xff) - 0xa0;
            return (p == plane);
        }

        public boolean isLegalReplacement(byte[] repl) {
            return true;
        }

        protected CoderResult encodeLoop(CharBuffer src, ByteBuffer dst) {
            char[] sa = src.array();
            int sp = src.arrayOffset() + src.position();
            int sl = src.arrayOffset() + src.limit();
            byte[] da = dst.array();
            int dp = dst.arrayOffset() + dst.position();
            int dl = dst.arrayOffset() + dst.limit();

            try {
                while (sp < sl) {
                    char c = sa[sp];
                    if ( c > '\u007f'&& c < '\uFFFE') {
                        int nb = toEUC(c, bb);
                        if (nb != -1) {
                            int p = 0;
                            if (nb == 4)
                                p = (bb[1] & 0xff) - 0xa0;
                            if (p == plane) {
                                if (dl - dp < 2)
                                    return CoderResult.OVERFLOW;
                                if (nb == 2) {
                                    da[dp++] = (byte)(bb[0] & 0x7f);
                                    da[dp++] = (byte)(bb[1] & 0x7f);
                                } else {
                                    da[dp++] = (byte)(bb[2] & 0x7f);
                                    da[dp++] = (byte)(bb[3] & 0x7f);
                                }
                                sp++;
                                continue;
                            }
                        }
                    }
                    return CoderResult.unmappableForLength(1);
                }
                return CoderResult.UNDERFLOW;
            } finally {
                src.position(sp - src.arrayOffset());
                dst.position(dp - dst.arrayOffset());
            }
        }
    }

    private class Decoder extends EUC_TW.Decoder {
        int plane;
        private String table;
        protected Decoder(Charset cs, int plane) {
            super(cs);
            if (plane == 0)
                this.plane = plane;
            else if (plane == 2 || plane == 3)
                this.plane = plane - 1;
            else
                throw new IllegalArgumentException
                    ("Only planes 1, 2, and 3 supported");
        }

        //we only work on array backed buffer.
        protected CoderResult decodeLoop(ByteBuffer src, CharBuffer dst) {
            byte[] sa = src.array();
            int sp = src.arrayOffset() + src.position();
            int sl = src.arrayOffset() + src.limit();

            char[] da = dst.array();
            int dp = dst.arrayOffset() + dst.position();
            int dl = dst.arrayOffset() + dst.limit();

            try {
                while (sp < sl) {
                    if ( sl - sp < 2) {
                        return CoderResult.UNDERFLOW;
                    }
                    int b1 = (sa[sp] & 0xff) | 0x80;
                    int b2 = (sa[sp + 1] & 0xff) | 0x80;
                    char[] cc = toUnicode(b1, b2, plane);
                    // plane3 has non-bmp characters(added), x11cnsp3
                    // however does not support them
                    if (cc == null || cc.length == 2)
                        return CoderResult.unmappableForLength(2);
                    if (dl - dp < 1)
                        return CoderResult.OVERFLOW;
                    da[dp++] = cc[0];
                    sp +=2;
                }
                return CoderResult.UNDERFLOW;
            } finally {
                src.position(sp - src.arrayOffset());
                dst.position(dp - dst.arrayOffset());
            }
        }
    }
}