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.SpringTransactionPolicy;
022 import org.apache.camel.spring.spi.TransactionErrorHandlerBuilder;
023 import org.springframework.context.ApplicationContext;
024 import org.springframework.context.ApplicationContextAware;
025 import org.springframework.transaction.PlatformTransactionManager;
026 import org.springframework.transaction.support.TransactionTemplate;
027
028 /**
029 * An extension of the {@link RouteBuilder} to provide some additional helper
030 * methods
031 *
032 * @version $Revision: 816070 $
033 */
034 public abstract class SpringRouteBuilder extends RouteBuilder implements ApplicationContextAware {
035 private ApplicationContext applicationContext;
036
037 /**
038 * Looks up the bean with the given name in the application context and
039 * returns it, or throws an exception if the bean is not present or is not
040 * of the given type
041 *
042 * @param beanName the name of the bean in the application context
043 * @param type the type of the bean
044 * @return the bean
045 */
046 @SuppressWarnings("unchecked")
047 public <T> T lookup(String beanName, Class<T> type) {
048 ApplicationContext context = getApplicationContext();
049 return (T)context.getBean(beanName, type);
050 }
051
052 /**
053 * Looks up the bean with the given type in the application context and
054 * returns it, or throws an exception if the bean is not present or there
055 * are multiple possible beans to choose from for the given type
056 *
057 * @param type the type of the bean
058 * @return the bean
059 */
060 @SuppressWarnings("unchecked")
061 public <T> T lookup(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 public ApplicationContext getApplicationContext() {
082 if (applicationContext == null) {
083 CamelContext camelContext = getContext();
084 if (camelContext instanceof SpringCamelContext) {
085 SpringCamelContext springCamelContext = (SpringCamelContext)camelContext;
086 return springCamelContext.getApplicationContext();
087 } else {
088 throw new IllegalArgumentException("This SpringBuilder is not being used with a SpringCamelContext and there is no applicationContext property configured");
089 }
090 }
091 return applicationContext;
092 }
093
094 /**
095 * Sets the application context to use to lookup beans
096 */
097 public void setApplicationContext(ApplicationContext applicationContext) {
098 this.applicationContext = applicationContext;
099 }
100
101 /**
102 * Creates a transaction error handler that will lookup in application context for
103 * an exiting transaction manager.
104 *
105 * @return the created error handler
106 */
107 public TransactionErrorHandlerBuilder transactionErrorHandler() {
108 return new TransactionErrorHandlerBuilder();
109 }
110
111 /**
112 * Creates a transaction error handler.
113 *
114 * @param policy using this transaction policy (eg: required, supports, ...)
115 * @return the created error handler
116 */
117 public TransactionErrorHandlerBuilder transactionErrorHandler(SpringTransactionPolicy policy) {
118 return transactionErrorHandler(policy.getTransactionTemplate());
119 }
120
121 /**
122 * Creates a transaction error handler.
123 *
124 * @param template the spring transaction template
125 * @return the created error handler
126 */
127 public TransactionErrorHandlerBuilder transactionErrorHandler(TransactionTemplate template) {
128 TransactionErrorHandlerBuilder answer = new TransactionErrorHandlerBuilder();
129 answer.setTransactionTemplate(template);
130 return answer;
131 }
132
133 /**
134 * Creates a transaction error handler.
135 *
136 * @param transactionManager the spring transaction manager
137 * @return the created error handler
138 */
139 public TransactionErrorHandlerBuilder transactionErrorHandler(PlatformTransactionManager transactionManager) {
140 TransactionTemplate template = new TransactionTemplate(transactionManager);
141 return transactionErrorHandler(template);
142 }
143
144 }