camel-core/src/test/java/org/apache/camel/processor/LoopWithAggregatorTest.java

/**
 * 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.camel.processor;

import org.apache.camel.ContextTestSupport;
import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.processor.aggregate.AggregationStrategy;

public class LoopWithAggregatorTest extends ContextTestSupport {

    public void testLoopCopy() throws Exception {
        getMockEndpoint("mock:loop").expectedBodiesReceived("AB", "AB", "AB");
        getMockEndpoint("mock:result").expectedBodiesReceived("AB");

        template.requestBody("direct:start", "A");

        assertMockEndpointsSatisfied();
    }

    @Override
    protected RouteBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            @Override
            public void configure() throws Exception {
                // START SNIPPET: e1
                from("direct:start")
                    // instruct loop to use copy mode, which mean it will use a copy of the input exchange
                    // for each loop iteration, instead of keep using the same exchange all over
                    .loop(3).copy()
                        .enrich("direct:getTimeStamp", new ExampleAggregationStrategy())
                        .inOnly("mock:loop")
                    .end()
                    .to("mock:result");
                // END SNIPPET: e1
                
                from("direct:getTimeStamp").process(new Processor() {

                    @Override
                    public void process(Exchange exchange) throws Exception {
                        // set the response directly
                        exchange.getIn().setBody("B");
                        
                    }
                    
                });
            }
        };
    }
    
    public static class ExampleAggregationStrategy implements AggregationStrategy {

        public Exchange aggregate(Exchange original, Exchange resource) {
            String originalBody = original.getIn().getBody(String.class);
            if (original.getOut().getBody() != null) {
                originalBody = original.getOut().getBody(String.class);
            }
            String resourceResponse = resource.getIn().getBody(String.class);
            String mergeResult = originalBody + resourceResponse;
            if (original.getPattern().isOutCapable()) {
                original.getOut().setBody(mergeResult);
            } else {
                original.getIn().setBody(mergeResult);
            }
            return original;
        }
        
    }

}