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A java-based parser for parsing/grabbing web sites and other text or XML documents, based on a nondeterministic parser language, creating XML output. Also contains a few utility classes for HTML, CSV and text parsing, and additional character sets. The jMatchParser-charset module contains the character sets.
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/*
* Copyright (c) 2010 - 2011 Michael Schierl
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - 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.
*
* - Neither name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND THE CONTRIBUTORS
* "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 THE COPYRIGHT
* HOLDERS OR THE 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.
*/
package net.sf.jmatchparser.util.charset;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CoderResult;
import java.util.Map;
class CombinationCharset extends Table8BitCharset {
private final String[] combinations;
private char[][] combinationsMap = null;
private float avgCharsPerByte = 0;
protected CombinationCharset(String canonicalName, String[] aliases, String mapping, String... combinations) {
super(canonicalName, aliases, mapping);
this.combinations = combinations;
}
@Override
public CharsetDecoder newDecoder() {
if (combinationsMap == null) {
combinationsMap = new char[256][];
int combinationCount = 0;
for (String combination : combinations) {
int first = combination.charAt(0);
combinationsMap[first] = combination.substring(1).toCharArray();
for (int i = 1; i < combination.length(); i++) {
if (combination.charAt(i) != '\uFFFD') {
combinationCount++;
}
}
}
avgCharsPerByte = (combinationCount * 1 + (65536 - combinationCount) * 2) / 65536f / 2f;
}
return new Decoder();
}
@Override
protected void addExtraItemsToEncoderMap(Map encoderMap) {
for (String combination : combinations) {
byte first = (byte) combination.charAt(0);
for (int i = 1; i < combination.length(); i++) {
char c = combination.charAt(i);
if (c != '\uFFFD') {
encoderMap.put(c, new byte[] { first, (byte) (i - 1) });
}
}
}
}
private class Decoder extends CharsetDecoder {
private int lastByte = -1;
protected Decoder() {
super(CombinationCharset.this, avgCharsPerByte, 2);
}
@Override
protected CoderResult decodeLoop(ByteBuffer in, CharBuffer out) {
while (true) {
if (in.remaining() == 0)
return CoderResult.UNDERFLOW;
if (out.remaining() == 0)
return CoderResult.OVERFLOW;
int b = in.get() & 0xFF;
if (lastByte != -1) {
char c = combinationsMap[lastByte][b];
if (c == '\uFFFD') {
// un-read the last character
in.position(in.position() - 1);
out.put(mapping.charAt(lastByte));
} else {
out.put(c);
}
lastByte = -1;
} else if (combinationsMap[b] != null) {
lastByte = b;
} else {
char c = mapping.charAt(b);
if (c == '\uFFFD') {
in.position(in.position() - 1);
return CoderResult.unmappableForLength(1);
}
out.put(c);
}
}
}
@Override
protected CoderResult implFlush(CharBuffer out) {
if (lastByte != -1) {
if (out.remaining() == 0)
return CoderResult.OVERFLOW;
out.put(mapping.charAt(lastByte));
lastByte = -1;
}
return super.implFlush(out);
}
@Override
protected void implReset() {
lastByte = -1;
}
}
}