/*
* Copyright 2002-2017 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.test.util;
import org.springframework.aop.framework.Advised;
import org.springframework.aop.support.AopUtils;
import org.springframework.util.Assert;
/**
* {@code AopTestUtils} is a collection of AOP-related utility methods for
* use in unit and integration testing scenarios.
*
* <p>For Spring's core AOP utilities, see
* {@link org.springframework.aop.support.AopUtils AopUtils} and
* {@link org.springframework.aop.framework.AopProxyUtils AopProxyUtils}.
*
* @author Sam Brannen
* @since 4.2
* @see org.springframework.aop.support.AopUtils
* @see org.springframework.aop.framework.AopProxyUtils
* @see ReflectionTestUtils
*/
public abstract class AopTestUtils {
/**
* Get the <em>target</em> object of the supplied {@code candidate} object.
* <p>If the supplied {@code candidate} is a Spring
* {@linkplain AopUtils#isAopProxy proxy}, the target of the proxy will
* be returned; otherwise, the {@code candidate} will be returned
* <em>as is</em>.
* @param candidate the instance to check (potentially a Spring AOP proxy;
* never {@code null})
* @return the target object or the {@code candidate} (never {@code null})
* @throws IllegalStateException if an error occurs while unwrapping a proxy
* @see Advised#getTargetSource()
* @see #getUltimateTargetObject
*/
@SuppressWarnings("unchecked")
public static <T> T getTargetObject(Object candidate) {
Assert.notNull(candidate, "Candidate must not be null");
try {
if (AopUtils.isAopProxy(candidate) && candidate instanceof Advised) {
return (T) ((Advised) candidate).getTargetSource().getTarget();
}
}
catch (Throwable ex) {
throw new IllegalStateException("Failed to unwrap proxied object", ex);
}
return (T) candidate;
}
/**
* Get the ultimate <em>target</em> object of the supplied {@code candidate}
* object, unwrapping not only a top-level proxy but also any number of
* nested proxies.
* <p>If the supplied {@code candidate} is a Spring
* {@linkplain AopUtils#isAopProxy proxy}, the ultimate target of all
* nested proxies will be returned; otherwise, the {@code candidate}
* will be returned <em>as is</em>.
* @param candidate the instance to check (potentially a Spring AOP proxy;
* never {@code null})
* @return the target object or the {@code candidate} (never {@code null})
* @throws IllegalStateException if an error occurs while unwrapping a proxy
* @see Advised#getTargetSource()
* @see org.springframework.aop.framework.AopProxyUtils#ultimateTargetClass
*/
@SuppressWarnings("unchecked")
public static <T> T getUltimateTargetObject(Object candidate) {
Assert.notNull(candidate, "Candidate must not be null");
try {
if (AopUtils.isAopProxy(candidate) && candidate instanceof Advised) {
return (T) getUltimateTargetObject(((Advised) candidate).getTargetSource().getTarget());
}
}
catch (Throwable ex) {
throw new IllegalStateException("Failed to unwrap proxied object", ex);
}
return (T) candidate;
}
}