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.camel.component.sql;
018    
019    import java.sql.PreparedStatement;
020    import java.sql.SQLException;
021    import java.util.Iterator;
022    import java.util.List;
023    
024    import org.apache.camel.Exchange;
025    import org.apache.camel.impl.DefaultProducer;
026    import org.springframework.dao.DataAccessException;
027    import org.springframework.jdbc.core.ColumnMapRowMapper;
028    import org.springframework.jdbc.core.JdbcTemplate;
029    import org.springframework.jdbc.core.PreparedStatementCallback;
030    import org.springframework.jdbc.core.RowMapperResultSetExtractor;
031    
032    public class SqlProducer extends DefaultProducer {
033        private String query;
034        private JdbcTemplate jdbcTemplate;
035    
036        public SqlProducer(SqlEndpoint endpoint, String query, JdbcTemplate jdbcTemplate) {
037            super(endpoint);
038            this.jdbcTemplate = jdbcTemplate;
039            this.query = query;
040        }
041    
042        public void process(final Exchange exchange) throws Exception {
043            jdbcTemplate.execute(query, new PreparedStatementCallback() {
044                public Object doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException {
045                    int argNumber = 1;
046    
047                    // number of parameters must match
048                    int expected = ps.getParameterMetaData().getParameterCount();
049    
050                    if (expected > 0 && exchange.getIn().getBody() != null) {
051                        Iterator<?> iterator = exchange.getIn().getBody(Iterator.class);
052                        while (iterator != null && iterator.hasNext()) {
053                            ps.setObject(argNumber++, iterator.next());
054                        }
055                    }
056    
057                    if (argNumber - 1 != expected) {
058                        throw new SQLException("Number of parameters mismatch. Expected: " + expected + ", was:" + (argNumber - 1));
059                    }
060                    
061                    boolean isResultSet = ps.execute();
062                    
063                    if (isResultSet) {
064                        RowMapperResultSetExtractor mapper = new RowMapperResultSetExtractor(new ColumnMapRowMapper());
065                        List<?> result = (List<?>) mapper.extractData(ps.getResultSet());
066                        exchange.getOut().setBody(result);
067                        exchange.getIn().setHeader(SqlConstants.SQL_ROW_COUNT, result.size());
068                        // preserve headers
069                        exchange.getOut().setHeaders(exchange.getIn().getHeaders());
070                    } else {
071                        exchange.getIn().setHeader(SqlConstants.SQL_UPDATE_COUNT, ps.getUpdateCount());
072                    }
073    
074                    // data is set on exchange so return null
075                    return null;
076                }
077            });
078        }
079    
080    }