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 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        public <T> T lookup(Class<T> type) {
060            ApplicationContext context = getApplicationContext();
061            return context.getBean(type);
062        }
063    
064        /**
065         * Returns the application context which has been configured via the
066         * {@link #setApplicationContext(ApplicationContext)} method or from the
067         * underlying {@link SpringCamelContext}
068         */
069        public ApplicationContext getApplicationContext() {
070            if (applicationContext == null) {
071                CamelContext camelContext = getContext();
072                if (camelContext instanceof SpringCamelContext) {
073                    SpringCamelContext springCamelContext = (SpringCamelContext)camelContext;
074                    return springCamelContext.getApplicationContext();
075                } else {
076                    throw new IllegalArgumentException("This SpringBuilder is not being used with a SpringCamelContext and there is no applicationContext property configured");
077                }
078            }
079            return applicationContext;
080        }
081    
082        /**
083         * Sets the application context to use to lookup beans
084         */
085        public void setApplicationContext(ApplicationContext applicationContext) {        
086            this.applicationContext = applicationContext;
087        }
088    
089        /**
090         * Creates a transaction error handler that will lookup in application context for
091         * an exiting transaction manager.
092         *
093         * @return the created error handler
094         */
095        public TransactionErrorHandlerBuilder transactionErrorHandler() {
096            return new TransactionErrorHandlerBuilder();
097        }
098    
099        /**
100         * Creates a transaction error handler.
101         *
102         * @param policy   using this transaction policy (eg: required, supports, ...)
103         * @return the created error handler
104         */
105        public TransactionErrorHandlerBuilder transactionErrorHandler(SpringTransactionPolicy policy) {
106            return transactionErrorHandler(policy.getTransactionTemplate());
107        }
108    
109        /**
110         * Creates a transaction error handler.
111         *
112         * @param template the spring transaction template
113         * @return the created error handler
114         */
115        public TransactionErrorHandlerBuilder transactionErrorHandler(TransactionTemplate template) {
116            TransactionErrorHandlerBuilder answer = new TransactionErrorHandlerBuilder();
117            answer.setTransactionTemplate(template);
118            return answer;
119        }
120    
121        /**
122         * Creates a transaction error handler.
123         *
124         * @param transactionManager the spring transaction manager
125         * @return the created error handler
126         */
127        public TransactionErrorHandlerBuilder transactionErrorHandler(PlatformTransactionManager transactionManager) {
128            TransactionTemplate template = new TransactionTemplate(transactionManager);
129            return transactionErrorHandler(template);
130        }
131    
132    }