org.springframework.aop.interceptor

Class AsyncExecutionAspectSupport

java.lang.Object

org.springframework.aop.interceptor.AsyncExecutionAspectSupport

All Implemented Interfaces:

Aware, BeanFactoryAware

Direct Known Subclasses:

AsyncExecutionInterceptor

public abstract class AsyncExecutionAspectSupport
extends Object
implements BeanFactoryAware

Base class for asynchronous method execution aspects, such as org.springframework.scheduling.annotation.AnnotationAsyncExecutionInterceptor or org.springframework.scheduling.aspectj.AnnotationAsyncExecutionAspect.

Provides support for executor qualification on a method-by-method basis. AsyncExecutionAspectSupport objects must be constructed with a default Executor, but each individual method may further qualify a specific Executor bean to be used when executing it, e.g. through an annotation attribute.

Since:

3.1.2

Author:

Chris Beams, Juergen Hoeller, Stephane Nicoll

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_TASK_EXECUTOR_BEAN_NAME The default name of the TaskExecutor bean to pick up: "taskExecutor".
protected Log	logger

Constructor Summary

Constructors

Constructor and Description
AsyncExecutionAspectSupport(Executor defaultExecutor) Create a new instance with a default AsyncUncaughtExceptionHandler.
AsyncExecutionAspectSupport(Executor defaultExecutor, AsyncUncaughtExceptionHandler exceptionHandler) Create a new AsyncExecutionAspectSupport with the given exception handler.

Method Summary

Modifier and Type	Method and Description
protected AsyncTaskExecutor	determineAsyncExecutor(Method method) Determine the specific executor to use when executing the given method.
protected Object	doSubmit(Callable<Object> task, AsyncTaskExecutor executor, Class<?> returnType) Delegate for actually executing the given task with the chosen executor.
protected Executor	findQualifiedExecutor(BeanFactory beanFactory, String qualifier) Retrieve a target executor for the given qualifier.
protected Executor	getDefaultExecutor(BeanFactory beanFactory) Retrieve or build a default executor for this advice instance.
protected abstract String	getExecutorQualifier(Method method) Return the qualifier or bean name of the executor to be used when executing the given async method, typically specified in the form of an annotation attribute.
protected void	handleError(Throwable ex, Method method, Object... params) Handles a fatal error thrown while asynchronously invoking the specified Method.
void	setBeanFactory(BeanFactory beanFactory) Set the BeanFactory to be used when looking up executors by qualifier or when relying on the default executor lookup algorithm.
void	setExceptionHandler(AsyncUncaughtExceptionHandler exceptionHandler) Supply the AsyncUncaughtExceptionHandler to use to handle exceptions thrown by invoking asynchronous methods with a void return type.
void	setExecutor(Executor defaultExecutor) Supply the executor to be used when executing async methods.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_TASK_EXECUTOR_BEAN_NAME

public static final String DEFAULT_TASK_EXECUTOR_BEAN_NAME

The default name of the TaskExecutor bean to pick up: "taskExecutor".

Note that the initial lookup happens by type; this is just the fallback in case of multiple executor beans found in the context.

Since:

4.2.6

See Also:

Constant Field Values

logger

protected final Log logger

Constructor Detail

AsyncExecutionAspectSupport

public AsyncExecutionAspectSupport(Executor defaultExecutor)

Create a new instance with a default AsyncUncaughtExceptionHandler.

Parameters:

defaultExecutor - the Executor (typically a Spring AsyncTaskExecutor or ExecutorService) to delegate to, unless a more specific executor has been requested via a qualifier on the async method, in which case the executor will be looked up at invocation time against the enclosing bean factory

AsyncExecutionAspectSupport

public AsyncExecutionAspectSupport(Executor defaultExecutor,
                                   AsyncUncaughtExceptionHandler exceptionHandler)

Create a new AsyncExecutionAspectSupport with the given exception handler.

Parameters:

defaultExecutor - the Executor (typically a Spring AsyncTaskExecutor or ExecutorService) to delegate to, unless a more specific executor has been requested via a qualifier on the async method, in which case the executor will be looked up at invocation time against the enclosing bean factory

exceptionHandler - the AsyncUncaughtExceptionHandler to use

Method Detail

setExecutor

public void setExecutor(Executor defaultExecutor)

Supply the executor to be used when executing async methods.

Parameters:

defaultExecutor - the Executor (typically a Spring AsyncTaskExecutor or ExecutorService) to delegate to, unless a more specific executor has been requested via a qualifier on the async method, in which case the executor will be looked up at invocation time against the enclosing bean factory

See Also:

getExecutorQualifier(Method), setBeanFactory(BeanFactory), getDefaultExecutor(BeanFactory)

setExceptionHandler

public void setExceptionHandler(AsyncUncaughtExceptionHandler exceptionHandler)

Supply the AsyncUncaughtExceptionHandler to use to handle exceptions thrown by invoking asynchronous methods with a void return type.

setBeanFactory

public void setBeanFactory(BeanFactory beanFactory)

Set the BeanFactory to be used when looking up executors by qualifier or when relying on the default executor lookup algorithm.

Specified by:

setBeanFactory in interface BeanFactoryAware

Parameters:

beanFactory - owning BeanFactory (never null). The bean can immediately call methods on the factory.

See Also:

findQualifiedExecutor(BeanFactory, String), getDefaultExecutor(BeanFactory)

determineAsyncExecutor

protected AsyncTaskExecutor determineAsyncExecutor(Method method)

Determine the specific executor to use when executing the given method. Should preferably return an AsyncListenableTaskExecutor implementation.

Returns:

the executor to use (or null, but just if no default executor is available)

getExecutorQualifier

protected abstract String getExecutorQualifier(Method method)

Return the qualifier or bean name of the executor to be used when executing the given async method, typically specified in the form of an annotation attribute. Returning an empty string or null indicates that no specific executor has been specified and that the default executor should be used.

Parameters:

method - the method to inspect for executor qualifier metadata

Returns:

the qualifier if specified, otherwise empty String or null

See Also:

determineAsyncExecutor(Method), findQualifiedExecutor(BeanFactory, String)

findQualifiedExecutor

protected Executor findQualifiedExecutor(BeanFactory beanFactory,
                                         String qualifier)

Retrieve a target executor for the given qualifier.

Parameters:

qualifier - the qualifier to resolve

Returns:

the target executor, or null if none available

Since:

4.2.6

See Also:

getExecutorQualifier(Method)

getDefaultExecutor

protected Executor getDefaultExecutor(BeanFactory beanFactory)

Retrieve or build a default executor for this advice instance. An executor returned from here will be cached for further use.

The default implementation searches for a unique TaskExecutor bean in the context, or for an Executor bean named "taskExecutor" otherwise. If neither of the two is resolvable, this implementation will return null.

Parameters:

beanFactory - the BeanFactory to use for a default executor lookup

Returns:

the default executor, or null if none available

Since:

4.2.6

See Also:

findQualifiedExecutor(BeanFactory, String), DEFAULT_TASK_EXECUTOR_BEAN_NAME

doSubmit

protected Object doSubmit(Callable<Object> task,
                          AsyncTaskExecutor executor,
                          Class<?> returnType)

Delegate for actually executing the given task with the chosen executor.

Parameters:

task - the task to execute

executor - the chosen executor

returnType - the declared return type (potentially a Future variant)

Returns:

the execution result (potentially a corresponding Future handle)

handleError

protected void handleError(Throwable ex,
                           Method method,
                           Object... params)
                    throws Exception

Handles a fatal error thrown while asynchronously invoking the specified Method.

If the return type of the method is a Future object, the original exception can be propagated by just throwing it at the higher level. However, for all other cases, the exception will not be transmitted back to the client. In that later case, the current AsyncUncaughtExceptionHandler will be used to manage such exception.

Parameters:

ex - the exception to handle

method - the method that was invoked

params - the parameters used to invoke the method

Throws:

Exception