org.springframework.aop.interceptor.AsyncExecutionInterceptor Maven / Gradle / Ivy

/*
 * 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
 *
 *      https://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.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 {@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.
 *
 * 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}).
 *
 * 
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.
 *
 * 
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 {@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 {@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.
	 * @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