/*
* Copyright 2002-2008 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.interceptor;
import java.lang.reflect.Method;
import java.util.Properties;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.NamedThreadLocal;
import org.springframework.transaction.NoTransactionException;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.TransactionSystemException;
import org.springframework.util.ClassUtils;
/**
* Base class for transactional aspects, such as the AOP Alliance
* {@link TransactionInterceptor} or an AspectJ aspect.
*
* <p>This enables the underlying Spring transaction infrastructure to be used
* easily to implement an aspect for any aspect system.
*
* <p>Subclasses are responsible for calling methods in this class in the
* correct order.
*
* <p>If no transaction name has been specified in the
* <code>TransactionAttribute</code>, the exposed name will be the
* <code>fully-qualified class name + "." + method name</code>
* (by default).
*
* <p>Uses the <b>Strategy</b> design pattern. A
* <code>PlatformTransactionManager</code> implementation will perform the
* actual transaction management, and a <code>TransactionAttributeSource</code>
* is used for determining transaction definitions.
*
* <p>A transaction aspect is serializable if it's
* <code>PlatformTransactionManager</code> and
* <code>TransactionAttributeSource</code> are serializable.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @since 1.1
* @see #setTransactionManager
* @see #setTransactionAttributes
* @see #setTransactionAttributeSource
*/
public abstract class TransactionAspectSupport implements InitializingBean {
// NOTE: This class must not implement Serializable because it serves as base
// class for AspectJ aspects (which are not allowed to implement Serializable)!
/**
* Holder to support the <code>currentTransactionStatus()</code> method,
* and to support communication between different cooperating advices
* (e.g. before and after advice) if the aspect involves more than a
* single method (as will be the case for around advice).
*/
private static final ThreadLocal transactionInfoHolder =
new NamedThreadLocal("Current aspect-driven transaction");
/**
* Subclasses can use this to return the current TransactionInfo.
* Only subclasses that cannot handle all operations in one method,
* such as an AspectJ aspect involving distinct before and after advice,
* need to use this mechanism to get at the current TransactionInfo.
* An around advice such as an AOP Alliance MethodInterceptor can hold a
* reference to the TransactionInfo throughout the aspect method.
* <p>A TransactionInfo will be returned even if no transaction was created.
* The <code>TransactionInfo.hasTransaction()</code> method can be used to query this.
* <p>To find out about specific transaction characteristics, consider using
* TransactionSynchronizationManager's <code>isSynchronizationActive()</code>
* and/or <code>isActualTransactionActive()</code> methods.
* @return TransactionInfo bound to this thread, or <code>null</code> if none
* @see TransactionInfo#hasTransaction()
* @see org.springframework.transaction.support.TransactionSynchronizationManager#isSynchronizationActive()
* @see org.springframework.transaction.support.TransactionSynchronizationManager#isActualTransactionActive()
*/
protected static TransactionInfo currentTransactionInfo() throws NoTransactionException {
return (TransactionInfo) transactionInfoHolder.get();
}
/**
* Return the transaction status of the current method invocation.
* Mainly intended for code that wants to set the current transaction
* rollback-only but not throw an application exception.
* @throws NoTransactionException if the transaction info cannot be found,
* because the method was invoked outside an AOP invocation context
*/
public static TransactionStatus currentTransactionStatus() throws NoTransactionException {
TransactionInfo info = currentTransactionInfo();
if (info == null) {
throw new NoTransactionException("No transaction aspect-managed TransactionStatus in scope");
}
return currentTransactionInfo().transactionStatus;
}
protected final Log logger = LogFactory.getLog(getClass());
/** Delegate used to create, commit and rollback transactions */
private PlatformTransactionManager transactionManager;
/** Helper used to find transaction attributes */
private TransactionAttributeSource transactionAttributeSource;
/**
* Set the transaction manager. This will perform actual
* transaction management: This class is just a way of invoking it.
*/
public void setTransactionManager(PlatformTransactionManager transactionManager) {
this.transactionManager = transactionManager;
}
/**
* Return the transaction manager.
*/
public PlatformTransactionManager getTransactionManager() {
return this.transactionManager;
}
/**
* Set properties with method names as keys and transaction attribute
* descriptors (parsed via TransactionAttributeEditor) as values:
* e.g. key = "myMethod", value = "PROPAGATION_REQUIRED,readOnly".
* <p>Note: Method names are always applied to the target class,
* no matter if defined in an interface or the class itself.
* <p>Internally, a NameMatchTransactionAttributeSource will be
* created from the given properties.
* @see #setTransactionAttributeSource
* @see TransactionAttributeEditor
* @see NameMatchTransactionAttributeSource
*/
public void setTransactionAttributes(Properties transactionAttributes) {
NameMatchTransactionAttributeSource tas = new NameMatchTransactionAttributeSource();
tas.setProperties(transactionAttributes);
this.transactionAttributeSource = tas;
}
/**
* Set multiple transaction attribute sources which are used to find transaction
* attributes. Will build a CompositeTransactionAttributeSource for the given sources.
* @see CompositeTransactionAttributeSource
* @see MethodMapTransactionAttributeSource
* @see NameMatchTransactionAttributeSource
* @see AttributesTransactionAttributeSource
* @see org.springframework.transaction.annotation.AnnotationTransactionAttributeSource
*/
public void setTransactionAttributeSources(TransactionAttributeSource[] transactionAttributeSources) {
this.transactionAttributeSource = new CompositeTransactionAttributeSource(transactionAttributeSources);
}
/**
* Set the transaction attribute source which is used to find transaction
* attributes. If specifying a String property value, a PropertyEditor
* will create a MethodMapTransactionAttributeSource from the value.
* @see TransactionAttributeSourceEditor
* @see MethodMapTransactionAttributeSource
* @see NameMatchTransactionAttributeSource
* @see AttributesTransactionAttributeSource
* @see org.springframework.transaction.annotation.AnnotationTransactionAttributeSource
*/
public void setTransactionAttributeSource(TransactionAttributeSource transactionAttributeSource) {
this.transactionAttributeSource = transactionAttributeSource;
}
/**
* Return the transaction attribute source.
*/
public TransactionAttributeSource getTransactionAttributeSource() {
return this.transactionAttributeSource;
}
/**
* Check that required properties were set.
*/
public void afterPropertiesSet() {
if (getTransactionManager() == null) {
throw new IllegalArgumentException("Property 'transactionManager' is required");
}
if (getTransactionAttributeSource() == null) {
throw new IllegalArgumentException(
"Either 'transactionAttributeSource' or 'transactionAttributes' is required: " +
"If there are no transactional methods, then don't use a transaction aspect.");
}
}
/**
* Create a transaction if necessary, based on the given method and class.
* <p>Performs a default TransactionAttribute lookup for the given method.
* @param method method about to execute
* @param targetClass class the method is on
* @return a TransactionInfo object, whether or not a transaction was created.
* The hasTransaction() method on TransactionInfo can be used to tell if there
* was a transaction created.
* @see #getTransactionAttributeSource()
*/
protected TransactionInfo createTransactionIfNecessary(Method method, Class targetClass) {
// If the transaction attribute is null, the method is non-transactional.
TransactionAttribute txAttr = getTransactionAttributeSource().getTransactionAttribute(method, targetClass);
return createTransactionIfNecessary(txAttr, methodIdentification(method));
}
/**
* Convenience method to return a String representation of this Method
* for use in logging. Can be overridden in subclasses to provide a
* different identifier for the given method.
* @param method the method we're interested in
* @return log message identifying this method
* @see org.springframework.util.ClassUtils#getQualifiedMethodName
*/
protected String methodIdentification(Method method) {
return ClassUtils.getQualifiedMethodName(method);
}
/**
* Create a transaction if necessary based on the given TransactionAttribute.
* <p>Allows callers to perform custom TransactionAttribute lookups through
* the TransactionAttributeSource.
* @param txAttr the TransactionAttribute (may be <code>null</code>)
* @param joinpointIdentification the fully qualified method name
* (used for monitoring and logging purposes)
* @return a TransactionInfo object, whether or not a transaction was created.
* The <code>hasTransaction()</code> method on TransactionInfo can be used to
* tell if there was a transaction created.
* @see #getTransactionAttributeSource()
*/
protected TransactionInfo createTransactionIfNecessary(
TransactionAttribute txAttr, final String joinpointIdentification) {
// If no name specified, apply method identification as transaction name.
if (txAttr != null && txAttr.getName() == null) {
txAttr = new DelegatingTransactionAttribute(txAttr) {
public String getName() {
return joinpointIdentification;
}
};
}
TransactionStatus status = null;
if (txAttr != null) {
PlatformTransactionManager tm = getTransactionManager();
if (tm != null) {
status = tm.getTransaction(txAttr);
}
else {
if (logger.isDebugEnabled()) {
logger.debug("Skipping transactional joinpoint [" + joinpointIdentification +
"] because no transaction manager has been configured");
}
}
}
return prepareTransactionInfo(txAttr, joinpointIdentification, status);
}
/**
* Prepare a TransactionInfo for the given attribute and status object.
* @param txAttr the TransactionAttribute (may be <code>null</code>)
* @param joinpointIdentification the fully qualified method name
* (used for monitoring and logging purposes)
* @param status the TransactionStatus for the current transaction
* @return the prepared TransactionInfo object
*/
protected TransactionInfo prepareTransactionInfo(
TransactionAttribute txAttr, String joinpointIdentification, TransactionStatus status) {
TransactionInfo txInfo = new TransactionInfo(txAttr, joinpointIdentification);
if (txAttr != null) {
// We need a transaction for this method
if (logger.isTraceEnabled()) {
logger.trace("Getting transaction for [" + txInfo.getJoinpointIdentification() + "]");
}
// The transaction manager will flag an error if an incompatible tx already exists
txInfo.newTransactionStatus(status);
}
else {
// The TransactionInfo.hasTransaction() method will return
// false. We created it only to preserve the integrity of
// the ThreadLocal stack maintained in this class.
if (logger.isTraceEnabled())
logger.trace("Don't need to create transaction for [" + joinpointIdentification +
"]: This method isn't transactional.");
}
// We always bind the TransactionInfo to the thread, even if we didn't create
// a new transaction here. This guarantees that the TransactionInfo stack
// will be managed correctly even if no transaction was created by this aspect.
txInfo.bindToThread();
return txInfo;
}
/**
* Execute after successful completion of call, but not after an exception was handled.
* Do nothing if we didn't create a transaction.
* @param txInfo information about the current transaction
*/
protected void commitTransactionAfterReturning(TransactionInfo txInfo) {
if (txInfo != null && txInfo.hasTransaction()) {
if (logger.isTraceEnabled()) {
logger.trace("Completing transaction for [" + txInfo.getJoinpointIdentification() + "]");
}
getTransactionManager().commit(txInfo.getTransactionStatus());
}
}
/**
* Handle a throwable, completing the transaction.
* We may commit or roll back, depending on the configuration.
* @param txInfo information about the current transaction
* @param ex throwable encountered
*/
protected void completeTransactionAfterThrowing(TransactionInfo txInfo, Throwable ex) {
if (txInfo != null && txInfo.hasTransaction()) {
if (logger.isTraceEnabled()) {
logger.trace("Completing transaction for [" + txInfo.getJoinpointIdentification() +
"] after exception: " + ex);
}
if (txInfo.transactionAttribute.rollbackOn(ex)) {
try {
getTransactionManager().rollback(txInfo.getTransactionStatus());
}
catch (TransactionSystemException ex2) {
logger.error("Application exception overridden by rollback exception", ex);
ex2.initApplicationException(ex);
throw ex2;
}
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;
}
}
else {
// We don't roll back on this exception.
// Will still roll back if TransactionStatus.isRollbackOnly() is true.
try {
getTransactionManager().commit(txInfo.getTransactionStatus());
}
catch (TransactionSystemException ex2) {
logger.error("Application exception overridden by commit exception", ex);
ex2.initApplicationException(ex);
throw ex2;
}
catch (RuntimeException ex2) {
logger.error("Application exception overridden by commit exception", ex);
throw ex2;
}
catch (Error err) {
logger.error("Application exception overridden by commit error", ex);
throw err;
}
}
}
}
/**
* Reset the TransactionInfo ThreadLocal.
* <p>Call this in all cases: exception or normal return!
* @param txInfo information about the current transaction (may be <code>null</code>)
*/
protected void cleanupTransactionInfo(TransactionInfo txInfo) {
if (txInfo != null) {
txInfo.restoreThreadLocalStatus();
}
}
/**
* Opaque object used to hold Transaction information. Subclasses
* must pass it back to methods on this class, but not see its internals.
*/
protected class TransactionInfo {
private final TransactionAttribute transactionAttribute;
private final String joinpointIdentification;
private TransactionStatus transactionStatus;
private TransactionInfo oldTransactionInfo;
public TransactionInfo(TransactionAttribute transactionAttribute, String joinpointIdentification) {
this.transactionAttribute = transactionAttribute;
this.joinpointIdentification = joinpointIdentification;
}
public TransactionAttribute getTransactionAttribute() {
return this.transactionAttribute;
}
/**
* Return a String representation of this joinpoint (usually a Method call)
* for use in logging.
*/
public String getJoinpointIdentification() {
return this.joinpointIdentification;
}
public void newTransactionStatus(TransactionStatus status) {
this.transactionStatus = status;
}
public TransactionStatus getTransactionStatus() {
return this.transactionStatus;
}
/**
* Return whether a transaction was created by this aspect,
* or whether we just have a placeholder to keep ThreadLocal stack integrity.
*/
public boolean hasTransaction() {
return (this.transactionStatus != null);
}
private void bindToThread() {
// Expose current TransactionStatus, preserving any existing TransactionStatus
// for restoration after this transaction is complete.
this.oldTransactionInfo = (TransactionInfo) transactionInfoHolder.get();
transactionInfoHolder.set(this);
}
private void restoreThreadLocalStatus() {
// Use stack to restore old transaction TransactionInfo.
// Will be null if none was set.
transactionInfoHolder.set(this.oldTransactionInfo);
}
public String toString() {
return this.transactionAttribute.toString();
}
}
}