/*

  * $Id: RegexpDefinitionPatternMatcher.java 795343 2009-07-18 11:26:09Z apetrelli $

  *

  * 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 org.apache.tiles.definition.pattern.regexp;

 import java.util.regex.Matcher;

 import java.util.regex.Pattern;

 import org.apache.tiles.Definition;

 import org.apache.tiles.definition.pattern.DefinitionPatternMatcher;

 import org.apache.tiles.definition.pattern.PatternUtil;

 /**

  * Matches regular expression patterns in definitions.

  *

  * @version $Rev: 795343 $ $Date: 2009-07-18 21:26:09 +1000 (Sat, 18 Jul 2009) $

  * @since 2.2.0

  */

 public class RegexpDefinitionPatternMatcher implements DefinitionPatternMatcher {

     /**

      * The pattern to match.

      */

     private Pattern pattern;

     /**

      * The definition to use as a basis.

      */

     private Definition definition;

     /**

      * Constructor.

      *

      * @param pattern The pattern to use, in string form.

      * @param definition The definition to use as a basis.

      * @since 2.2.0

      */

     public RegexpDefinitionPatternMatcher(String pattern, Definition definition) {

         this.pattern = Pattern.compile(pattern);

         this.definition = definition;

     }

     /** {@inheritDoc} */

     public Definition createDefinition(String definitionName) {

         Definition retValue = null;

         Matcher matcher = pattern.matcher(definitionName);

         if (matcher.matches()) {

             int groupCount = matcher.groupCount() + 1;

             Object[] vars = new Object[groupCount];

             for (int i = 0; i < groupCount; i++) {

                 vars[i] = matcher.group(i);

             }

             retValue = PatternUtil.replacePlaceholders(definition,

                     definitionName, vars);

         }

         return retValue;

     }

 }