| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package com.opensymphony.xwork2.util; |
| |
| import java.util.regex.Pattern; |
| |
| /** |
| * Helper class to convert wildcard expression to regular expression |
| */ |
| public class WildcardUtil { |
| |
| /** |
| * Convert wildcard pattern to Pattern |
| * @param pattern String containing wildcard pattern |
| * @return compiled regular expression as a Pattern |
| */ |
| public static Pattern compileWildcardPattern(String pattern) { |
| StringBuilder buf = new StringBuilder(pattern); |
| |
| for (int i=buf.length()-1; i>=0; i--) |
| { |
| char c = buf.charAt(i); |
| if (c == '*' && (i == 0 || buf.charAt(i-1) != '\\')) |
| { |
| buf.insert(i+1, '?'); |
| buf.insert(i, '.'); |
| } |
| else if (c == '*') |
| { |
| i--; // skip backslash, too |
| } |
| else if (needsBackslashToBeLiteralInRegex(c)) |
| { |
| buf.insert(i, '\\'); |
| } |
| } |
| |
| return Pattern.compile(buf.toString()); |
| } |
| |
| /** |
| * @param c character to test |
| * @return true if the given character must be escaped to be a literal |
| * inside a regular expression. |
| */ |
| |
| private static final String theSpecialRegexCharList = ".[]\\?*+{}|()^$"; |
| |
| public static boolean needsBackslashToBeLiteralInRegex( |
| char c) |
| { |
| return (theSpecialRegexCharList.indexOf(c) >= 0); |
| } |
| |
| } |