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 */
017package org.apache.camel.spring;
018
019import org.apache.camel.CamelContext;
020import org.apache.camel.builder.RouteBuilder;
021import org.apache.camel.spring.spi.SpringTransactionPolicy;
022import org.apache.camel.spring.spi.TransactionErrorHandlerBuilder;
023import org.springframework.context.ApplicationContext;
024import org.springframework.context.ApplicationContextAware;
025import org.springframework.transaction.PlatformTransactionManager;
026import 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 */
034public 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}