bytetocharascii.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 95 行

/*
 * @(#)ByteToCharASCII.java	1.14 06/10/10
 *
 * Copyright  1990-2008 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 sun.io;

/**
 * A algorithmic conversion from ASCII to Unicode
 *
 * @author Limin Shi
 */
public class ByteToCharASCII extends ByteToCharConverter {

    // Return the character set id
    public String getCharacterEncoding()
    {
        return "ASCII";
    }

    public int flush(char[] output, int outStart, int outEnd) {
	// This converter will not buffer any data.
	byteOff = charOff = 0;
	return 0;
    }

    /**
     * Algorithmic character conversion
     */
    public int convert(byte[] input, int inOff, int inEnd,
		       char[] output, int outOff, int outEnd)
        throws ConversionBufferFullException, UnknownCharacterException
    {
        byte    inputByte;

        charOff = outOff;
        byteOff = inOff;

        // Loop until we hit the end of the input
        while(byteOff < inEnd)
        {
	    // If we don't have room for the output, throw an exception
	    if (charOff >= outEnd)
		throw new ConversionBufferFullException();

            // Convert the input byte
            inputByte = input[byteOff++];

            if (inputByte >= 0)
            	output[charOff++] = (char)inputByte;
            else {
                if (subMode)
                    output[charOff++] = '\uFFFD';	// Replace Char
                else {
                    badInputLength = 1;
                    throw new UnknownCharacterException();
                }
            }
        }

    	// Return the length written to the output buffer
	return charOff-outOff;
    }

    /*
     *   Reset after finding bad input
     */
    public void reset() {
	byteOff = charOff = 0;
    }

}