org.springframework.transaction.support.TransactionTemplate Maven / Gradle / Ivy
/*
* Copyright 2002-2005 the original author or authors.
*
* 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.springframework.transaction.support;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionException;
import org.springframework.transaction.TransactionStatus;
/**
* Helper class that simplifies programmatic transaction demarcation
* and transaction exception handling.
*
* The central method is "execute", supporting transactional code implementing
* the TransactionCallback interface. It handles the transaction lifecycle and
* possible exceptions such that neither the TransactionCallback implementation
* nor the calling code needs to explicitly handle transactions.
*
*
Typical usage: Allows for writing low-level application services that use
* (JNDI) resources but are not transaction-aware themselves. Instead, they
* can implicitly take part in (JTA) transactions handled by higher-level
* application services utilizing this class, making calls to the low-level
* services via an inner-class callback object.
*
*
Can be used within a service implementation via direct instantiation with
* a transaction manager reference, or get prepared in an application context
* and given to services as bean reference. Note: The transaction manager should
* always be configured as bean in the application context, in the first case
* given to the service directly, in the second case to the prepared template.
*
*
Supports setting the propagation behavior and the isolation level by name,
* for convenient configuration in context definitions.
*
* @author Juergen Hoeller
* @since 17.03.2003
* @see org.springframework.transaction.support.TransactionCallback
* @see org.springframework.transaction.PlatformTransactionManager
* @see org.springframework.transaction.jta.JtaTransactionManager
*/
public class TransactionTemplate extends DefaultTransactionDefinition implements InitializingBean{
protected final Log logger = LogFactory.getLog(getClass());
private PlatformTransactionManager transactionManager = null;
/**
* Create a new TransactionTemplate instance.
* Mainly targetted at configuration by a bean factory.
* Note: Transaction manager property needs to be set before any execute calls.
* @see #setTransactionManager
*/
public TransactionTemplate() {
}
/**
* Create a new TransactionTemplate instance.
* @param transactionManager transaction management strategy to be used
*/
public TransactionTemplate(PlatformTransactionManager transactionManager) {
this.transactionManager = transactionManager;
}
/**
* Set the transaction management strategy to be used.
*/
public void setTransactionManager(PlatformTransactionManager transactionManager) {
this.transactionManager = transactionManager;
}
/**
* Return the transaction management strategy to be used.
*/
public PlatformTransactionManager getTransactionManager() {
return transactionManager;
}
public void afterPropertiesSet() {
if (this.transactionManager == null) {
throw new IllegalArgumentException("transactionManager is required");
}
}
/**
* Execute the action specified by the given callback object within a transaction.
*
Allows for returning a result object created within the transaction, i.e.
* a domain object or a collection of domain objects. A RuntimeException thrown
* by the callback is treated as application exception that enforces a rollback.
* An exception gets propagated to the caller of the template.
* @param action callback object that specifies the transactional action
* @return a result object returned by the callback, or null
* @throws TransactionException in case of initialization, rollback, or system errors
*/
public Object execute(TransactionCallback action) throws TransactionException {
TransactionStatus status = this.transactionManager.getTransaction(this);
Object result = null;
try {
result = action.doInTransaction(status);
}
catch (RuntimeException ex) {
// transactional code threw application exception -> rollback
rollbackOnException(status, ex);
throw ex;
}
catch (Error err) {
// transactional code threw error -> rollback
rollbackOnException(status, err);
throw err;
}
this.transactionManager.commit(status);
return result;
}
/**
* Perform a rollback, handling rollback exceptions properly.
* @param status object representing the transaction
* @param ex the thrown application exception or error
* @throws TransactionException in case of a rollback error
*/
private void rollbackOnException(TransactionStatus status, Throwable ex) throws TransactionException {
if (logger.isDebugEnabled()) {
logger.debug("Initiating transaction rollback on application exception", ex);
}
try {
this.transactionManager.rollback(status);
}
catch (RuntimeException ex2) {
logger.error("Application exception overridden by rollback exception", ex);
throw ex2;
}
catch (Error err) {
logger.error("Application exception overridden by rollback error", ex);
throw err;
}
}
}