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.TransactionErrorHandler;
023 import org.apache.camel.spring.spi.TransactionErrorHandlerBuilder;
024 import org.springframework.context.ApplicationContext;
025 import org.springframework.context.ApplicationContextAware;
026 import org.springframework.transaction.PlatformTransactionManager;
027 import org.springframework.transaction.support.TransactionTemplate;
028
029 /**
030 * An extension of the {@link RouteBuilder} to provide some additional helper
031 * methods
032 *
033 * @version $Revision: 784803 $
034 */
035 public abstract class SpringRouteBuilder extends RouteBuilder implements ApplicationContextAware {
036 private ApplicationContext applicationContext;
037
038 /**
039 * Looks up the bean with the given name in the application context and
040 * returns it, or throws an exception if the bean is not present or is not
041 * of the given type
042 *
043 * @param beanName the name of the bean in the application context
044 * @param type the type of the bean
045 * @return the bean
046 */
047 @SuppressWarnings("unchecked")
048 public <T> T lookup(String beanName, Class<T> type) {
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 @SuppressWarnings("unchecked")
062 public <T> T lookup(Class<T> type) {
063 ApplicationContext context = getApplicationContext();
064 String[] names = context.getBeanNamesForType(type, true, true);
065 if (names != null) {
066 int count = names.length;
067 if (count == 1) {
068 // lets instantiate the single bean
069 return (T)context.getBean(names[0]);
070 } else if (count > 1) {
071 throw new IllegalArgumentException("Too many beans in the application context of type: " + type + ". Found: " + count);
072 }
073 }
074 throw new IllegalArgumentException("No bean available in the application context of type: " + type);
075 }
076
077 /**
078 * Returns the application context which has been configured via the
079 * {@link #setApplicationContext(ApplicationContext)} method or from the
080 * underlying {@link SpringCamelContext}
081 */
082 public ApplicationContext getApplicationContext() {
083 if (applicationContext == null) {
084 CamelContext camelContext = getContext();
085 if (camelContext instanceof SpringCamelContext) {
086 SpringCamelContext springCamelContext = (SpringCamelContext)camelContext;
087 return springCamelContext.getApplicationContext();
088 } else {
089 throw new IllegalArgumentException("This SpringBuilder is not being used with a SpringCamelContext and there is no applicationContext property configured");
090 }
091 }
092 return applicationContext;
093 }
094
095 /**
096 * Sets the application context to use to lookup beans
097 */
098 public void setApplicationContext(ApplicationContext applicationContext) {
099 this.applicationContext = applicationContext;
100 }
101
102 /**
103 * Creates a transaction error handler that will lookup in application context for
104 * an exiting transaction manager.
105 *
106 * @return the created error handler
107 */
108 public TransactionErrorHandlerBuilder transactionErrorHandler() {
109 return new TransactionErrorHandlerBuilder();
110 }
111
112 /**
113 * Creates a transaction error handler.
114 *
115 * @param policy using this transaction policy (eg: required, supports, ...)
116 * @return the created error handler
117 */
118 public TransactionErrorHandlerBuilder transactionErrorHandler(SpringTransactionPolicy policy) {
119 return transactionErrorHandler(policy.getTransactionTemplate());
120 }
121
122 /**
123 * Creates a transaction error handler.
124 *
125 * @param template the spring transaction template
126 * @return the created error handler
127 */
128 public TransactionErrorHandlerBuilder transactionErrorHandler(TransactionTemplate template) {
129 TransactionErrorHandlerBuilder answer = new TransactionErrorHandlerBuilder();
130 answer.setTransactionTemplate(template);
131 return answer;
132 }
133
134 /**
135 * Creates a transaction error handler.
136 *
137 * @param transactionManager the spring transaction manager
138 * @return the created error handler
139 */
140 public TransactionErrorHandlerBuilder transactionErrorHandler(PlatformTransactionManager transactionManager) {
141 TransactionTemplate template = new TransactionTemplate(transactionManager);
142 return transactionErrorHandler(template);
143 }
144
145 }