/**
* Logback: the reliable, generic, fast and flexible logging framework.
* Copyright (C) 1999-2013, QOS.ch. All rights reserved.
*
* This program and the accompanying materials are dual-licensed under
* either the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation
*
* or (per the licensee's choosing)
*
* under the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation.
*/
package ch.qos.logback.core.util;
/**
* This class supports mapping character sequences to
* regular expressions as appropriate for SimpleDateFormatter.
*
* @author Ceki
*
*/
class CharSequenceToRegexMapper {
String toRegex(CharSequenceState css) {
final int occurrences = css.occurrences;
final char c = css.c;
switch (css.c) {
case 'G':
case 'z':
return ".*";
case 'M':
if (occurrences >= 3) {
return ".{3,12}";
} else {
return number(occurrences);
}
case 'y':
case 'w':
case 'W':
case 'D':
case 'd':
case 'F':
case 'H':
case 'k':
case 'K':
case 'h':
case 'm':
case 's':
case 'S':
return number(occurrences);
case 'E':
return ".{2,12}";
case 'a':
return ".{2}";
case 'Z':
return "(\\+|-)\\d{4}";
case '.':
return "\\.";
case '\\':
throw new IllegalStateException("Forward slashes are not allowed");
case '\'':
if (occurrences == 1) {
return "";
}
throw new IllegalStateException("Too many single quotes");
default:
if (occurrences == 1) {
return "" + c;
} else {
return c + "{" + occurrences + "}";
}
}
}
private String number(int occurrences) {
return "\\d{" + occurrences + "}";
}
}