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
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 public <T> T lookup(String beanName, Class<T> type) {
047 ApplicationContext context = getApplicationContext();
048 return (T)context.getBean(beanName, type);
049 }
050
051 /**
052 * Looks up the bean with the given type in the application context and
053 * returns it, or throws an exception if the bean is not present or there
054 * are multiple possible beans to choose from for the given type
055 *
056 * @param type the type of the bean
057 * @return the bean
058 */
059 @SuppressWarnings("unchecked")
060 public <T> T lookup(Class<T> type) {
061 ApplicationContext context = getApplicationContext();
062 String[] names = context.getBeanNamesForType(type, true, true);
063 if (names != null) {
064 int count = names.length;
065 if (count == 1) {
066 // lets instantiate the single bean
067 return (T)context.getBean(names[0]);
068 } else if (count > 1) {
069 throw new IllegalArgumentException("Too many beans in the application context of type: " + type + ". Found: " + count);
070 }
071 }
072 throw new IllegalArgumentException("No bean available in the application context of type: " + type);
073 }
074
075 /**
076 * Returns the application context which has been configured via the
077 * {@link #setApplicationContext(ApplicationContext)} method or from the
078 * underlying {@link SpringCamelContext}
079 */
080 public ApplicationContext getApplicationContext() {
081 if (applicationContext == null) {
082 CamelContext camelContext = getContext();
083 if (camelContext instanceof SpringCamelContext) {
084 SpringCamelContext springCamelContext = (SpringCamelContext)camelContext;
085 return springCamelContext.getApplicationContext();
086 } else {
087 throw new IllegalArgumentException("This SpringBuilder is not being used with a SpringCamelContext and there is no applicationContext property configured");
088 }
089 }
090 return applicationContext;
091 }
092
093 /**
094 * Sets the application context to use to lookup beans
095 */
096 public void setApplicationContext(ApplicationContext applicationContext) {
097 this.applicationContext = applicationContext;
098 }
099
100 /**
101 * Creates a transaction error handler that will lookup in application context for
102 * an exiting transaction manager.
103 *
104 * @return the created error handler
105 */
106 public TransactionErrorHandlerBuilder transactionErrorHandler() {
107 return new TransactionErrorHandlerBuilder();
108 }
109
110 /**
111 * Creates a transaction error handler.
112 *
113 * @param policy using this transaction policy (eg: required, supports, ...)
114 * @return the created error handler
115 */
116 public TransactionErrorHandlerBuilder transactionErrorHandler(SpringTransactionPolicy policy) {
117 return transactionErrorHandler(policy.getTransactionTemplate());
118 }
119
120 /**
121 * Creates a transaction error handler.
122 *
123 * @param template the spring transaction template
124 * @return the created error handler
125 */
126 public TransactionErrorHandlerBuilder transactionErrorHandler(TransactionTemplate template) {
127 TransactionErrorHandlerBuilder answer = new TransactionErrorHandlerBuilder();
128 answer.setTransactionTemplate(template);
129 return answer;
130 }
131
132 /**
133 * Creates a transaction error handler.
134 *
135 * @param transactionManager the spring transaction manager
136 * @return the created error handler
137 */
138 public TransactionErrorHandlerBuilder transactionErrorHandler(PlatformTransactionManager transactionManager) {
139 TransactionTemplate template = new TransactionTemplate(transactionManager);
140 return transactionErrorHandler(template);
141 }
142
143 }