utf_16be_writer.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 89 行

/*
 *
 *
 * Copyright  1990-2007 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 *
 * This program 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.
 *
 * This program 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 at /legal/license.txt).
 *
 * 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 or visit www.sun.com if you need additional
 * information or have any questions.
 */

package com.sun.cldc.i18n.j2me;

import java.io.*;

/**
 * Writer for Big Endian UTF-16 encoded output streams.
 * We assume that character strings
 * are correctly converted to UFT-16, so no additional checking is performed.
 */
public class UTF_16BE_Writer extends com.sun.cldc.i18n.StreamWriter {

    /**
     * Write a portion of an array of characters.
     *
     * @param  cbuf  Array of characters
     * @param  off   Offset from which to start writing characters
     * @param  len   Number of characters to write
     *
     * @exception  IOException  If an I/O error occurs
     */
    public void write(char cbuf[], int off, int len) throws IOException {
        byte[] outputBytes = new byte[2];
        int inputChar;
        int count = 0;

        while (count < len) {
            inputChar = 0xffff & cbuf[off + count];
            charToBytes(inputChar, outputBytes);
            out.write(outputBytes, 0, 2);
            count++;
        }
    }

    /**
     * Convert a 16-bit character into two bytes.
     * (This class uses the Big Endian byte order);
     * @param inputChar character to convert
     * @param outputBytes the array receiving the two bytes
     */
    protected void charToBytes(int inputChar, byte[] outputBytes) {
        outputBytes[0] = (byte) (0xFF&(inputChar>>8));
        outputBytes[1] = (byte) (0xFF&inputChar);
    }

    /**
     * Get the size in bytes of an array of chars.
     *
     * @param      array  Source buffer
     * @param      offset Offset at which to start counting character sizes
     * @param      length number of bytes to use for counting
     *
     * @return     number of bytes that the characters would be converted to
     */
    /* The class Helper will ask the writer for the size the output will be.
     * Since chars already are in utf16, calculation is simple. */
    public int sizeOf(char[] array, int offset, int length) {
        return length << 1;
    }
}