ch.qos.cal10n.util.LexicalUtil Maven / Gradle / Ivy
/*
* Copyright (c) 2009 QOS.ch All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package ch.qos.cal10n.util;
/**
* @author Ceki Gücü
*/
public class LexicalUtil {
public static StringBuilder convertSpecialCharacters(StringBuilder inBuf) {
int i = inBuf.indexOf("\\");
if (i == -1) {
return inBuf;
}
StringBuilder outBuf = new StringBuilder(inBuf.length());
int followIndex = -1; // index of char following the latest backslash
while (i != -1) {
outBuf.append(inBuf.subSequence(followIndex + 1, i));
followIndex = i + 1;
char c = inBuf.charAt(followIndex);
switch (c) {
case 'u':
char unicodeChar = readUnicode(inBuf, followIndex + 1);
outBuf.append(unicodeChar);
followIndex += 4;
break;
case 'n':
outBuf.append('\n');
break;
case 'r':
outBuf.append('\r');
break;
case 't':
outBuf.append('\t');
break;
case 'f':
outBuf.append('\f');
break;
case ':': // see http://tinyurl.com/bprdgnk , i.e. the javadocs for Properties.store()
case '#':
case '!':
case '=':
outBuf.append(c);
break;
default:
outBuf.append('\\');
outBuf.append(c);
}
// search for the next \
i = inBuf.indexOf("\\", followIndex + 1);
}
outBuf.append(inBuf.subSequence(followIndex + 1, inBuf.length()));
return outBuf;
}
// see http://java.sun.com/docs/books/jls/second_edition/html/lexical.doc.html#95504
private static char readUnicode(StringBuilder inBuf, int i) {
int r = 0;
for (int j = i; j < i + 4; j++) {
char atJ = inBuf.charAt(j);
if (atJ >= '0' && atJ <= '9') {
r = (r << 4) + atJ - '0';
continue;
}
if (atJ >= 'A' && atJ <= 'F') {
// '7' = 'A' - 10
r = (r << 4) + atJ - '7';
continue;
}
if (atJ >= 'a' && atJ <= 'f') {
// 'W' = 'a' - 10
r = (r << 4) + atJ - 'W';
continue;
}
}
return (char) r;
}
}