/**************************************************************************
* Copyright (c) 2001 by Punch Telematix. All rights reserved. *
* *
* Redistribution and use in source and binary forms, with or without *
* modification, are permitted provided that the following conditions *
* are met: *
* 1. Redistributions of source code must retain the above copyright *
* notice, this list of conditions and the following disclaimer. *
* 2. Redistributions in binary form must reproduce the above copyright *
* notice, this list of conditions and the following disclaimer in the *
* documentation and/or other materials provided with the distribution. *
* 3. Neither the name of Punch Telematix nor the names of *
* other contributors may be used to endorse or promote products *
* derived from this software without specific prior written permission.*
* *
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED *
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF *
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. *
* IN NO EVENT SHALL PUNCH TELEMATIX OR OTHER CONTRIBUTORS BE LIABLE *
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR *
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF *
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR *
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, *
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE *
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN *
* IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *
**************************************************************************/
/*
** $Id: UTF16Decoder.java,v 1.1.1.1 2004/07/12 14:07:47 cvs Exp $
*/
package wonka.decoders;
import java.io.*;
public class UTF16Decoder extends Decoder {
private int state;
private void setEndianness(InputStream in) throws IOException {
int b1 = in.read();
int b2 = in.read();
if (b1 == 0xfe && b2 == 0xff) {
state = BIGEND;
}
else if (b1 == 0xff && b2 == 0xfe) {
state = LITTLEEND;
}
else {
throw new UTFDataFormatException("missing BOM");
}
}
public char[] bToC(byte[] bytes, int off, int len){
if(len < 2){
return new char[0];
}
int c = bytes[off++];
c = ((c<<8) | (bytes[off++] & 0xff)) & 0xffff;
if(c == 0xfffe){ //LITTLE END
return UnicodeDecoder.leBToC(bytes,off,len-2);
}
if(c == 0xfeff){ //BIGEND
return UnicodeDecoder.beBToC(bytes,off, len-2);
}
return UnicodeDecoder.beBToC(bytes, off-2, len);
}
public int cFromStream(InputStream in, char[] chars, int off, int len) throws IOException {
if(state == UNDEFINED){
setEndianness(in);
}
int l = 2*len;
byte[] bytes = new byte[l];
int rd = in.read(bytes, 0 , l);
if(rd == -1){
return -1;
}
if(rd % 2 == 1){
int b = in.read();
if(b != -1){
bytes[rd++] = (byte)b;
}
else {
rd--;
}
}
int i = 0;
if(state == BIGEND){
while(i < rd){
int ch = bytes[i++]<<8;
chars[off++] = (char) ((ch | (bytes[i++] & 0xff)) & 0xffff);
}
}
else {
while(i < rd){
int ch = bytes[i++] & 0xff;
chars[off++] = (char) ((ch | (bytes[i++]<<8)) & 0xffff);
}
}
return rd/2;
}
public byte[] cToB(char[] chars, int off, int len){
byte[] bytes = new byte[len*2 + 2];
len += off;
bytes[0] = (byte)0xfe;
bytes[1] = (byte)0xff;
int o = 2;
for(int i = off; i < len ; i++){
int ch = chars[i];
bytes[o++] = (byte)(ch>>8);
bytes[o++] = (byte)ch;
}
return bytes;
}
public int getChar(InputStream in) throws IOException {
if(state == UNDEFINED){
setEndianness(in);
}
int b1 = in.read();
if(b1 == -1){
return -1;
}
int b2 = in.read();
if(b2 == -1){
return -1;
}
if(state == BIGEND){
return (b1<<8) | b2;
}
return (b2<<8) | b1;
}
public String getEncoding(){
return "UTF16";
}
}