/*
* Copyright 2004-2006 Graeme Rocher
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.grails.transaction;
import grails.core.GrailsApplication;
import grails.transaction.TransactionManagerAware;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
import org.springframework.core.Ordered;
import org.springframework.core.PriorityOrdered;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.util.Assert;
/**
* Injects the platform transaction manager into beans that implement {@link grails.transaction.TransactionManagerAware}.
*
* @author Graeme Rocher
* @since 0.4
*/
public class TransactionManagerPostProcessor extends InstantiationAwareBeanPostProcessorAdapter implements BeanFactoryAware, PriorityOrdered {
private ConfigurableListableBeanFactory beanFactory;
private PlatformTransactionManager transactionManager;
private int order = Ordered.LOWEST_PRECEDENCE;
private boolean initialized = false;
/**
* Gets the platform transaction manager from the bean factory if
* there is one.
* @param beanFactory The bean factory handling this post processor.
* @throws BeansException
*/
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
Assert.isInstanceOf(ConfigurableListableBeanFactory.class, beanFactory,
"TransactionManagerPostProcessor requires a ConfigurableListableBeanFactory");
this.beanFactory = (ConfigurableListableBeanFactory) beanFactory;
}
/**
* Injects the platform transaction manager into the given bean if
* that bean implements the {@link grails.transaction.TransactionManagerAware} interface.
* @param bean The bean to process.
* @param name The name of the bean.
* @return The bean after the transaction manager has been injected.
* @throws BeansException
*/
@Override
public boolean postProcessAfterInstantiation(Object bean, String name) throws BeansException {
if (bean instanceof TransactionManagerAware) {
initialize();
if(transactionManager != null) {
TransactionManagerAware tma = (TransactionManagerAware) bean;
tma.setTransactionManager(transactionManager);
}
}
return true;
}
private void initialize() {
if(transactionManager == null && beanFactory != null && !initialized) {
if (beanFactory.containsBean(GrailsApplication.TRANSACTION_MANAGER_BEAN)) {
transactionManager = beanFactory.getBean(GrailsApplication.TRANSACTION_MANAGER_BEAN, PlatformTransactionManager.class);
} else {
// Fetch the names of all the beans that are of type
// PlatformTransactionManager. Note that we have to pass
// "false" for the last argument to avoid eager initialisation,
// otherwise we end up in an endless loop (it triggers the current method).
String[] beanNames = BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
beanFactory, PlatformTransactionManager.class, false, false);
// If at least one is found, use the first of them as the
// transaction manager for the application.
if (beanNames.length > 0) {
transactionManager = (PlatformTransactionManager)beanFactory.getBean(beanNames[0]);
}
}
initialized = true;
}
}
public int getOrder() {
return order;
}
}