001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.activemq.console.filter;
018    
019    import java.util.ArrayList;
020    import java.util.Iterator;
021    import java.util.List;
022    
023    public abstract class WildcardTransformFilter extends AbstractQueryFilter {
024    
025        /**
026         * Creates a wildcard transform filter that is able to convert a wildcard
027         * expression (determined by isWildcardQuery) to a another query type (use
028         * transformWildcardQuery).
029         * 
030         * @param next - the next query filter
031         */
032        protected WildcardTransformFilter(QueryFilter next) {
033            super(next);
034        }
035    
036        /**
037         * Converts the query list to set of different queries
038         * 
039         * @param queries - query list to transform
040         * @return - result of the query
041         * @throws Exception
042         */
043        public List query(List queries) throws Exception {
044            List newQueries = new ArrayList();
045    
046            for (Iterator i = queries.iterator(); i.hasNext();) {
047                String queryToken = (String)i.next();
048    
049                // Transform the wildcard query
050                if (isWildcardQuery(queryToken)) {
051                    // Transform the value part only
052                    newQueries.add(transformWildcardQuery(queryToken));
053    
054                    // Maintain the query as is
055                } else {
056                    newQueries.add(queryToken);
057                }
058            }
059    
060            return next.query(newQueries);
061        }
062    
063        /**
064         * Use to determine is a query string is a wildcard query
065         * 
066         * @param query - query string
067         * @return true, if the query string is a wildcard query, false otherwise
068         */
069        protected abstract boolean isWildcardQuery(String query);
070    
071        /**
072         * Use to transform a wildcard query string to another query format
073         * 
074         * @param query - query string to transform
075         * @return transformed query
076         */
077        protected abstract String transformWildcardQuery(String query);
078    }