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.aws.sdb;
018    
019    import com.amazonaws.services.simpledb.AmazonSimpleDB;
020    import com.amazonaws.services.simpledb.model.SelectRequest;
021    import com.amazonaws.services.simpledb.model.SelectResult;
022    
023    import org.apache.camel.Exchange;
024    import org.apache.camel.Message;
025    
026    public class SelectCommand extends AbstractSdbCommand {
027    
028        public SelectCommand(AmazonSimpleDB sdbClient, SdbConfiguration configuration, Exchange exchange) {
029            super(sdbClient, configuration, exchange);
030        }
031    
032        public void execute() {
033            SelectRequest request = new SelectRequest()
034                .withSelectExpression(determineSelectExpression())
035                .withConsistentRead(determineConsistentRead())
036                .withNextToken(determineNextToken());
037            log.trace("Sending request [{}] for exchange [{}]...", request, exchange);
038            
039            SelectResult result = this.sdbClient.select(request);
040            
041            log.trace("Received result [{}]", result);
042            
043            Message msg = getMessageForResponse(exchange);
044            msg.setHeader(SdbConstants.ITEMS, result.getItems());
045            msg.setHeader(SdbConstants.NEXT_TOKEN, result.getNextToken());
046        }
047    
048        protected String determineSelectExpression() {
049            return exchange.getIn().getHeader(SdbConstants.SELECT_EXPRESSION, String.class);
050        }
051    }