/*
* Copyright 2002-2018 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.
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package org.springframework.aop.interceptor;
import java.lang.reflect.Method;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.springframework.aop.support.AopUtils;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.core.BridgeMethodResolver;
import org.springframework.core.Ordered;
import org.springframework.core.task.AsyncTaskExecutor;
import org.springframework.core.task.SimpleAsyncTaskExecutor;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
AOP Alliance MethodInterceptor that processes method invocations asynchronously, using a given AsyncTaskExecutor. Typically used with the Async annotation. In terms of target method signatures, any parameter types are supported. However, the return type is constrained to either void or java.util.concurrent.Future. In the latter case, the Future handle returned from the proxy will be an actual asynchronous Future that can be used to track the result of the asynchronous method execution. However, since the target method needs to implement the same signature, it will have to return a temporary Future handle that just passes the return value through (like Spring's AsyncResult or EJB 3.1's javax.ejb.AsyncResult).
When the return type is java.util.concurrent.Future, any exception thrown during the execution can be accessed and managed by the caller. With void return type however, such exceptions cannot be transmitted back. In that case an AsyncUncaughtExceptionHandler can be registered to process such exceptions.
As of Spring 3.1.2 the AnnotationAsyncExecutionInterceptor subclass is preferred for use due to its support for executor qualification in conjunction with Spring's @Async annotation.
Author: Juergen Hoeller, Chris Beams, Stephane Nicoll See Also: - Async
- AsyncAnnotationAdvisor
- AnnotationAsyncExecutionInterceptor
Since: 3.0
/**
* AOP Alliance {@code MethodInterceptor} that processes method invocations
* asynchronously, using a given {@link org.springframework.core.task.AsyncTaskExecutor}.
* Typically used with the {@link org.springframework.scheduling.annotation.Async} annotation.
*
* <p>In terms of target method signatures, any parameter types are supported.
* However, the return type is constrained to either {@code void} or
* {@code java.util.concurrent.Future}. In the latter case, the Future handle
* returned from the proxy will be an actual asynchronous Future that can be used
* to track the result of the asynchronous method execution. However, since the
* target method needs to implement the same signature, it will have to return
* a temporary Future handle that just passes the return value through
* (like Spring's {@link org.springframework.scheduling.annotation.AsyncResult}
* or EJB 3.1's {@code javax.ejb.AsyncResult}).
*
* <p>When the return type is {@code java.util.concurrent.Future}, any exception thrown
* during the execution can be accessed and managed by the caller. With {@code void}
* return type however, such exceptions cannot be transmitted back. In that case an
* {@link AsyncUncaughtExceptionHandler} can be registered to process such exceptions.
*
* <p>As of Spring 3.1.2 the {@code AnnotationAsyncExecutionInterceptor} subclass is
* preferred for use due to its support for executor qualification in conjunction with
* Spring's {@code @Async} annotation.
*
* @author Juergen Hoeller
* @author Chris Beams
* @author Stephane Nicoll
* @since 3.0
* @see org.springframework.scheduling.annotation.Async
* @see org.springframework.scheduling.annotation.AsyncAnnotationAdvisor
* @see org.springframework.scheduling.annotation.AnnotationAsyncExecutionInterceptor
*/
public class AsyncExecutionInterceptor extends AsyncExecutionAspectSupport implements MethodInterceptor, Ordered {
Create a new instance with a default AsyncUncaughtExceptionHandler. Params: - defaultExecutor – the
Executor (typically a Spring AsyncTaskExecutor or ExecutorService) to delegate to; as of 4.2.6, a local executor for this interceptor will be built otherwise
/**
* Create a new instance with a default {@link AsyncUncaughtExceptionHandler}.
* @param defaultExecutor the {@link Executor} (typically a Spring {@link AsyncTaskExecutor}
* or {@link java.util.concurrent.ExecutorService}) to delegate to;
* as of 4.2.6, a local executor for this interceptor will be built otherwise
*/
public AsyncExecutionInterceptor(@Nullable Executor defaultExecutor) {
super(defaultExecutor);
}
Create a new AsyncExecutionInterceptor. Params: - defaultExecutor – the
Executor (typically a Spring AsyncTaskExecutor or ExecutorService) to delegate to; as of 4.2.6, a local executor for this interceptor will be built otherwise - exceptionHandler – the
AsyncUncaughtExceptionHandler to use
/**
* Create a new {@code AsyncExecutionInterceptor}.
* @param defaultExecutor the {@link Executor} (typically a Spring {@link AsyncTaskExecutor}
* or {@link java.util.concurrent.ExecutorService}) to delegate to;
* as of 4.2.6, a local executor for this interceptor will be built otherwise
* @param exceptionHandler the {@link AsyncUncaughtExceptionHandler} to use
*/
public AsyncExecutionInterceptor(@Nullable Executor defaultExecutor, AsyncUncaughtExceptionHandler exceptionHandler) {
super(defaultExecutor, exceptionHandler);
}
Intercept the given method invocation, submit the actual calling of the method to
the correct task executor and return immediately to the caller.
Params: - invocation – the method to intercept and make asynchronous
Returns: Future if the original method returns Future; null otherwise.
/**
* Intercept the given method invocation, submit the actual calling of the method to
* the correct task executor and return immediately to the caller.
* @param invocation the method to intercept and make asynchronous
* @return {@link Future} if the original method returns {@code Future}; {@code null}
* otherwise.
*/
@Override
@Nullable
public Object invoke(final MethodInvocation invocation) throws Throwable {
Class<?> targetClass = (invocation.getThis() != null ? AopUtils.getTargetClass(invocation.getThis()) : null);
Method specificMethod = ClassUtils.getMostSpecificMethod(invocation.getMethod(), targetClass);
final Method userDeclaredMethod = BridgeMethodResolver.findBridgedMethod(specificMethod);
AsyncTaskExecutor executor = determineAsyncExecutor(userDeclaredMethod);
if (executor == null) {
throw new IllegalStateException(
"No executor specified and no default executor set on AsyncExecutionInterceptor either");
}
Callable<Object> task = () -> {
try {
Object result = invocation.proceed();
if (result instanceof Future) {
return ((Future<?>) result).get();
}
}
catch (ExecutionException ex) {
handleError(ex.getCause(), userDeclaredMethod, invocation.getArguments());
}
catch (Throwable ex) {
handleError(ex, userDeclaredMethod, invocation.getArguments());
}
return null;
};
return doSubmit(task, executor, invocation.getMethod().getReturnType());
}
This implementation is a no-op for compatibility in Spring 3.1.2.
Subclasses may override to provide support for extracting qualifier information,
e.g. via an annotation on the given method.
See Also: Returns: always null Since: 3.1.2
/**
* This implementation is a no-op for compatibility in Spring 3.1.2.
* Subclasses may override to provide support for extracting qualifier information,
* e.g. via an annotation on the given method.
* @return always {@code null}
* @since 3.1.2
* @see #determineAsyncExecutor(Method)
*/
@Override
@Nullable
protected String getExecutorQualifier(Method method) {
return null;
}
This 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 (e.g. if no BeanFactory was configured at all), this implementation falls back to a newly created SimpleAsyncTaskExecutor instance for local use if no default could be found. See Also:
/**
* This implementation searches for a unique {@link org.springframework.core.task.TaskExecutor}
* bean in the context, or for an {@link Executor} bean named "taskExecutor" otherwise.
* If neither of the two is resolvable (e.g. if no {@code BeanFactory} was configured at all),
* this implementation falls back to a newly created {@link SimpleAsyncTaskExecutor} instance
* for local use if no default could be found.
* @see #DEFAULT_TASK_EXECUTOR_BEAN_NAME
*/
@Override
@Nullable
protected Executor getDefaultExecutor(@Nullable BeanFactory beanFactory) {
Executor defaultExecutor = super.getDefaultExecutor(beanFactory);
return (defaultExecutor != null ? defaultExecutor : new SimpleAsyncTaskExecutor());
}
@Override
public int getOrder() {
return Ordered.HIGHEST_PRECEDENCE;
}
}