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.spring;
018
019 import org.apache.camel.CamelContext;
020 import org.apache.camel.builder.RouteBuilder;
021 import org.apache.camel.spring.spi.TransactionInterceptor;
022
023 import org.springframework.context.ApplicationContext;
024 import org.springframework.transaction.support.TransactionTemplate;
025
026 /**
027 * An extension of the {@link RouteBuilder} to provide some additional helper
028 * methods
029 *
030 * @version $Revision: 1.1 $
031 */
032 public abstract class SpringRouteBuilder extends RouteBuilder {
033 private ApplicationContext applicationContext;
034
035 public TransactionInterceptor transactionInterceptor() {
036 return new TransactionInterceptor(bean(TransactionTemplate.class));
037 }
038
039 /**
040 * Looks up the bean with the given name in the application context and
041 * returns it, or throws an exception if the bean is not present or is not
042 * of the given type
043 *
044 * @param type the type of the bean
045 * @param beanName the name of the bean in the application context
046 * @return the bean
047 */
048 public <T> T bean(Class<T> type, String beanName) {
049 ApplicationContext context = getApplicationContext();
050 return (T)context.getBean(beanName, type);
051 }
052
053 /**
054 * Looks up the bean with the given type in the application context and
055 * returns it, or throws an exception if the bean is not present or there
056 * are multiple possible beans to choose from for the given type
057 *
058 * @param type the type of the bean
059 * @return the bean
060 */
061 public <T> T bean(Class<T> type) {
062 ApplicationContext context = getApplicationContext();
063 String[] names = context.getBeanNamesForType(type, true, true);
064 if (names != null) {
065 int count = names.length;
066 if (count == 1) {
067 // lets instantiate the single bean
068 return (T)context.getBean(names[0]);
069 } else if (count > 1) {
070 throw new IllegalArgumentException("Too many beans in the application context of type: " + type + ". Found: " + count);
071 }
072 }
073 throw new IllegalArgumentException("No bean available in the application context of type: " + type);
074 }
075
076 /**
077 * Returns the application context which has been configured via the
078 * {@link #setApplicationContext(ApplicationContext)} method or from the
079 * underlying {@link SpringCamelContext}
080 *
081 * @return
082 */
083 public ApplicationContext getApplicationContext() {
084 if (applicationContext == null) {
085 CamelContext camelContext = getContext();
086 if (camelContext instanceof SpringCamelContext) {
087 SpringCamelContext springCamelContext = (SpringCamelContext)camelContext;
088 return springCamelContext.getApplicationContext();
089 } else {
090 throw new IllegalArgumentException("This SpringBuilder is not being used with a SpringCamelContext and there is no applicationContext property configured");
091 }
092 }
093 return applicationContext;
094 }
095
096 /**
097 * Sets the application context to use to lookup beans
098 */
099 public void setApplicationContext(ApplicationContext applicationContext) {
100 this.applicationContext = applicationContext;
101 }
102 }