/*
* Copyright (c) 2013-2017, Parallel Universe Software Co. 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 3.0
* as published by the Free Software Foundation.
*/
package co.paralleluniverse.common.util;
import java.util.regex.Pattern;
/**
*
* @author pron
*/
public final class Strings {
@SuppressWarnings("fallthrough")
public static String globToRegex(String pattern) {
// Based on Neil Traft: http://stackoverflow.com/a/17369948/750563
final String DOT = ".";
final StringBuilder out = new StringBuilder(pattern.length());
out.append('^');
int inGroup = 0;
int inClass = 0;
int firstIndexInClass = -1;
char[] arr = pattern.toCharArray();
for (int i = 0; i < arr.length; i++) {
char ch = arr[i];
switch (ch) {
case '\\':
if (++i >= arr.length) {
out.append('\\');
} else {
char next = arr[i];
switch (next) {
case ',':
// escape not needed
break;
case 'Q':
case 'E':
// extra escape needed
out.append('\\');
default:
out.append('\\');
}
out.append(next);
}
break;
case '*':
if (inClass == 0)
out.append(DOT + "*");
else
out.append('*');
break;
case '?':
if (inClass == 0)
out.append(DOT);
else
out.append('?');
break;
case '[':
inClass++;
firstIndexInClass = i + 1;
out.append('[');
break;
case ']':
inClass--;
out.append(']');
break;
case '.':
case '(':
case ')':
case '+':
case '|':
case '^':
case '$':
case '@':
case '%':
if (inClass == 0 || (firstIndexInClass == i && ch == '^'))
out.append('\\');
out.append(ch);
break;
case '!':
if (firstIndexInClass == i)
out.append('^');
else
out.append('!');
break;
case '{':
inGroup++;
out.append('(');
break;
case '}':
inGroup--;
out.append(')');
break;
case ',':
if (inGroup > 0)
out.append('|');
else
out.append(',');
break;
default:
out.append(ch);
}
}
out.append('$');
return out.toString();
}
// public static final String globToRegex(String glob) {
// StringBuilder out = new StringBuilder(glob.length() + 5);
// out.append('^');
// for (int i = 0; i < glob.length(); ++i) {
// final char c = glob.charAt(i);
// switch (c) {
// case '*':
// out.append(".*");
// break;
// case '?':
// out.append('.');
// break;
// case '.':
// out.append("\\.");
// break;
// case '\\':
// out.append("\\\\");
// break;
// default:
// out.append(c);
// }
// }
// out.append('$');
//
// return out.toString();
// }
public static final Pattern globToPattern(String glob) {
return Pattern.compile(globToRegex(glob));
}
private Strings() {
}
}