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.commons.dbutils.handlers;
018    
019    import java.sql.ResultSet;
020    import java.sql.SQLException;
021    import java.util.ArrayList;
022    import java.util.List;
023    
024    import org.apache.commons.dbutils.ResultSetHandler;
025    
026    /**
027     * Abstract class that simplify development of <code>ResultSetHandler</code>
028     * classes that convert <code>ResultSet</code> into <code>List</code>.
029     *
030     * @see org.apache.commons.dbutils.ResultSetHandler
031     */
032    public abstract class AbstractListHandler implements ResultSetHandler {
033        /**
034         * Whole <code>ResultSet</code> handler. It produce <code>List</code> as
035         * result. To convert individual rows into Java objects it uses
036         * <code>handleRow(ResultSet)</code> method.
037         *
038         * @see #handleRow(ResultSet)
039         */
040        public Object handle(ResultSet rs) throws SQLException {
041            List rows = new ArrayList();
042            while (rs.next()) {
043                rows.add(this.handleRow(rs));
044            }
045            return rows;
046        }
047        
048        /**
049         * Row handler. Method converts current row into some Java object.
050         *
051         * @param rs <code>ResultSet</code> to process.
052         * @return row processing result
053         * @throws SQLException error occurs
054         */
055        protected abstract Object handleRow(ResultSet rs) throws SQLException;
056    }