org.springframework.scheduling.aspectj.AnnotationAsyncExecutionAspect.aj Maven / Gradle / Ivy
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* Copyright 2002-2024 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
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package org.springframework.scheduling.aspectj;
import java.lang.reflect.Method;
import java.util.concurrent.Future;
import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.scheduling.annotation.Async;
/**
* Aspect to route methods based on Spring's {@link Async} annotation.
*
* This aspect routes methods marked with the {@link Async} annotation as well as methods
* in classes marked with the same. Any method expected to be routed asynchronously must
* return either {@code void}, {@link Future}, or a subtype of {@link Future} (in particular,
* {@link java.util.concurrent.CompletableFuture}). This aspect, therefore, will produce a
* compile-time error for methods that violate this constraint on the return type. If,
* however, a class marked with {@code @Async} contains a method that violates this
* constraint, it produces only a warning.
*
*
This aspect needs to be injected with an implementation of a task-oriented
* {@link java.util.concurrent.Executor} to activate it for a specific thread pool,
* or with a {@link org.springframework.beans.factory.BeanFactory} for default
* executor lookup. Otherwise it will simply delegate all calls synchronously.
*
* @author Ramnivas Laddad
* @author Chris Beams
* @since 3.0.5
* @see #setExecutor
* @see #setBeanFactory
* @see #getDefaultExecutor
*/
public aspect AnnotationAsyncExecutionAspect extends AbstractAsyncExecutionAspect {
private pointcut asyncMarkedMethod() : execution(@Async (void || Future+) *(..));
private pointcut asyncTypeMarkedMethod() : execution((void || Future+) (@Async *).*(..));
public pointcut asyncMethod() : asyncMarkedMethod() || asyncTypeMarkedMethod();
/**
* This implementation inspects the given method and its declaring class for the
* {@code @Async} annotation, returning the qualifier value expressed by {@link Async#value()}.
* If {@code @Async} is specified at both the method and class level, the method's
* {@code #value} takes precedence (even if empty string, indicating that the default
* executor should be used preferentially).
* @return the qualifier if specified, otherwise empty string indicating that the
* {@linkplain #setExecutor default executor} should be used
* @see #determineAsyncExecutor(Method)
*/
@Override
protected String getExecutorQualifier(Method method) {
// Maintainer's note: changes made here should also be made in
// AnnotationAsyncExecutionInterceptor#getExecutorQualifier
Async async = AnnotatedElementUtils.findMergedAnnotation(method, Async.class);
if (async == null) {
async = AnnotatedElementUtils.findMergedAnnotation(method.getDeclaringClass(), Async.class);
}
return (async != null ? async.value() : null);
}
declare error:
execution(@Async !(void || Future+) *(..)):
"Only methods that return void or Future may have an @Async annotation";
declare warning:
execution(!(void || Future+) (@Async *).*(..)):
"Methods in a class marked with @Async that do not return void or Future will be routed synchronously";
}