/*****************************************************************************
* Copyright (C) The Apache Software Foundation. All rights reserved. *
* ------------------------------------------------------------------------- *
* This software is published under the terms of the Apache Software License *
* version 1.1, a copy of which has been included with this distribution in *
* the LICENSE file. *
*****************************************************************************/
package org.apache.batik.xml;
import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;
import java.io.Reader;
import org.apache.batik.util.io.StreamNormalizingReader;
import org.apache.batik.util.io.UTF16Decoder;
/**
* This class represents a normalizing reader with encoding detection
* management.
*
* @author <a href="mailto:stephane@hillion.org">Stephane Hillion</a>
* @version $Id: XMLStreamNormalizingReader.java,v 1.3 2003/04/11 13:59:39 vhardy Exp $
*/
public class XMLStreamNormalizingReader extends StreamNormalizingReader {
/**
* Creates a new XMLStreamNormalizingReader.
* @param is The input stream to read.
* @param encod The character encoding to use if the auto-detection fail.
*/
public XMLStreamNormalizingReader(InputStream is, String encod)
throws IOException {
PushbackInputStream pbis = new PushbackInputStream(is, 128);
byte[] buf = new byte[4];
int len = pbis.read(buf);
if (len > 0) {
pbis.unread(buf, 0, len);
}
if (len == 4) {
switch (buf[0] & 0x00FF) {
case 0:
if (buf[1] == 0x003c && buf[2] == 0x0000 && buf[3] == 0x003f) {
charDecoder = new UTF16Decoder(pbis, true);
return;
}
break;
case '<':
switch (buf[1] & 0x00FF) {
case 0:
if (buf[2] == 0x003f && buf[3] == 0x0000) {
charDecoder = new UTF16Decoder(pbis, false);
return;
}
break;
case '?':
if (buf[2] == 'x' && buf[3] == 'm') {
Reader r = XMLUtilities.createXMLDeclarationReader
(pbis, "UTF8");
String enc = XMLUtilities.getXMLDeclarationEncoding
(r, "UTF-8");
charDecoder = createCharDecoder(pbis, enc);
return;
}
}
break;
case 0x004C:
if (buf[1] == 0x006f &&
(buf[2] & 0x00FF) == 0x00a7 &&
(buf[3] & 0x00FF) == 0x0094) {
Reader r = XMLUtilities.createXMLDeclarationReader
(pbis, "CP037");
String enc = XMLUtilities.getXMLDeclarationEncoding
(r, "EBCDIC-CP-US");
charDecoder = createCharDecoder(pbis, enc);
return;
}
break;
case 0x00FE:
if ((buf[1] & 0x00FF) == 0x00FF) {
charDecoder = createCharDecoder(pbis, "UTF-16");
return;
}
break;
case 0x00FF:
if ((buf[1] & 0x00FF) == 0x00FE) {
charDecoder = createCharDecoder(pbis, "UTF-16");
return;
}
}
}
encod = (encod == null) ? "UTF-8" : encod;
charDecoder = createCharDecoder(pbis, encod);
}
}