/*
 * Copyright 2004-2011 the Seasar Foundation and the Others.
 *
 * Licensed 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 org.seasar.teeda.core.util;

import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author shot
 * 
 */
public class PatternUtil {

    private static Map patternCache = new HashMap();

    private PatternUtil() {
    }

    public static Pattern getPattern(String regex) {
        Pattern pattern = (Pattern) patternCache.get(regex);
        if (pattern == null) {
            pattern = Pattern.compile(regex);
            patternCache.put(regex, pattern);
        }
        return pattern;
    }

    public static boolean matches(String regex, CharSequence value) {
        if (regex == null) {
            throw new IllegalArgumentException("regex");
        }
        Pattern pattern = getPattern(regex);
        Matcher matcher = pattern.matcher(value);
        return matcher.matches();
    }

    public static void clearPatternCache() {
        patternCache.clear();
    }
}
