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.bean;
018    
019    import java.lang.reflect.InvocationHandler;
020    import java.lang.reflect.InvocationTargetException;
021    import java.lang.reflect.Method;
022    
023    import org.apache.camel.Endpoint;
024    import org.apache.camel.Exchange;
025    import org.apache.camel.ExchangePattern;
026    import org.apache.camel.Producer;
027    import org.apache.camel.impl.DefaultExchange;
028    
029    /**
030     * An {@link java.lang.reflect.InvocationHandler} which invokes a
031     * message exchange on a camel {@link Endpoint}
032     *
033     * @version $Revision: 733079 $
034     */
035    public class CamelInvocationHandler implements InvocationHandler {
036        private final Endpoint endpoint;
037        private final Producer producer;
038        private final MethodInfoCache methodInfoCache;
039    
040        public CamelInvocationHandler(Endpoint endpoint, Producer producer, MethodInfoCache methodInfoCache) {
041            this.endpoint = endpoint;
042            this.producer = producer;
043            this.methodInfoCache = methodInfoCache;
044        }
045    
046        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
047            BeanInvocation invocation = new BeanInvocation(method, args);
048            ExchangePattern pattern = ExchangePattern.InOut;
049            MethodInfo methodInfo = methodInfoCache.getMethodInfo(method);
050            if (methodInfo != null) {
051                pattern = methodInfo.getPattern();
052            }
053            Exchange exchange = new DefaultExchange(endpoint, pattern);
054            exchange.getIn().setBody(invocation);
055    
056            producer.process(exchange);
057            Throwable fault = exchange.getException();
058            if (fault != null) {
059                throw new InvocationTargetException(fault);
060            }
061            if (pattern.isOutCapable()) {
062                return exchange.getOut(true).getBody();
063            } else {
064                return null;
065            }
066        }
067    }
068