cn.taketoday.aop.framework.Advised Maven / Gradle / Ivy
/*
* Original Author -> Harry Yang ([email protected]) https://taketoday.cn
* Copyright © TODAY & 2017 - 2023 All Rights Reserved.
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see [http://www.gnu.org/licenses/]
*/
package cn.taketoday.aop.framework;
import org.aopalliance.aop.Advice;
import cn.taketoday.aop.Advisor;
import cn.taketoday.aop.IntroductionAdvisor;
import cn.taketoday.aop.TargetClassAware;
import cn.taketoday.aop.TargetSource;
import cn.taketoday.aop.support.DefaultPointcutAdvisor;
/**
* Interface to be implemented by classes that hold the configuration
* of a factory of AOP proxies. This configuration includes the
* Interceptors and other advice, Advisors, and the proxied interfaces.
*
* Any AOP proxy obtained from can be cast to this interface to
* allow manipulation of its AOP advice.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @author TODAY 2021/2/1 19:03
* @see AdvisedSupport
* @since 3.0
*/
public interface Advised extends TargetClassAware {
Advisor[] EMPTY_ADVISORS = new Advisor[0];
/**
* Return whether the Advised configuration is frozen,
* in which case no advice changes can be made.
*/
boolean isFrozen();
/**
* Are we proxying the full target class instead of specified interfaces?
*/
boolean isProxyTargetClass();
/**
* Return the interfaces proxied by the AOP proxy.
*
Will not include the target class, which may also be proxied.
*/
Class[] getProxiedInterfaces();
/**
* Determine whether the given interface is proxied.
*
* @param intf the interface to check
*/
boolean isInterfaceProxied(Class intf);
/**
* Change the {@code TargetSource} used by this {@code Advised} object.
*
Only works if the configuration isn't {@linkplain #isFrozen frozen}.
*
* @param targetSource new TargetSource to use
*/
void setTargetSource(TargetSource targetSource);
/**
* Return the {@code TargetSource} used by this {@code Advised} object.
*/
TargetSource getTargetSource();
/**
* Set whether the proxy should be exposed by the AOP framework as a
* {@link ThreadLocal} for retrieval via the {@link AopContext} class.
*
It can be necessary to expose the proxy if an advised object needs
* to invoke a method on itself with advice applied. Otherwise, if an
* advised object invokes a method on {@code this}, no advice will be applied.
*
Default is {@code false}, for optimal performance.
*/
void setExposeProxy(boolean exposeProxy);
/**
* Return whether the factory should expose the proxy as a {@link ThreadLocal}.
*
It can be necessary to expose the proxy if an advised object needs
* to invoke a method on itself with advice applied. Otherwise, if an
* advised object invokes a method on {@code this}, no advice will be applied.
*
Getting the proxy is analogous to an EJB calling {@code getEJBObject()}.
*
* @see AopContext
*/
boolean isExposeProxy();
/**
* Set whether this proxy configuration is pre-filtered so that it only
* contains applicable advisors (matching this proxy's target class).
*
Default is "false". Set this to "true" if the advisors have been
* pre-filtered already, meaning that the ClassFilter check can be skipped
* when building the actual advisor chain for proxy invocations.
*
* @see cn.taketoday.aop.ClassFilter
*/
void setPreFiltered(boolean preFiltered);
/**
* Return whether this proxy configuration is pre-filtered so that it only
* contains applicable advisors (matching this proxy's target class).
*/
boolean isPreFiltered();
/**
* Return the advisors applying to this proxy.
*
* @return an array of Advisors applying to this proxy (never {@code null})
*/
Advisor[] getAdvisors();
/**
* Return the number of advisors applying to this proxy.
*
The default implementation delegates to {@code getAdvisors().length}.
*/
default int getAdvisorCount() {
return getAdvisors().length;
}
/**
* Add an advisor at the end of the advisor chain.
*
The Advisor may be an {@link cn.taketoday.aop.IntroductionAdvisor},
* in which new interfaces will be available when a proxy is next obtained
* from the relevant factory.
*
* @param advisor the advisor to add to the end of the chain
* @throws AopConfigException in case of invalid advice
*/
void addAdvisor(Advisor advisor) throws AopConfigException;
/**
* Add an Advisor at the specified position in the chain.
*
* @param advisor the advisor to add at the specified position in the chain
* @param pos position in chain (0 is head). Must be valid.
* @throws AopConfigException in case of invalid advice
*/
void addAdvisor(int pos, Advisor advisor) throws AopConfigException;
/**
* Remove the given advisor.
*
* @param advisor the advisor to remove
* @return {@code true} if the advisor was removed; {@code false}
* if the advisor was not found and hence could not be removed
*/
boolean removeAdvisor(Advisor advisor);
/**
* Remove the advisor at the given index.
*
* @param index the index of advisor to remove
* @throws AopConfigException if the index is invalid
*/
void removeAdvisor(int index) throws AopConfigException;
/**
* Return the index (from 0) of the given advisor,
* or -1 if no such advisor applies to this proxy.
*
The return value of this method can be used to index into the advisors array.
*
* @param advisor the advisor to search for
* @return index from 0 of this advisor, or -1 if there's no such advisor
*/
int indexOf(Advisor advisor);
/**
* Replace the given advisor.
*
Note: If the advisor is an {@link IntroductionAdvisor}
* and the replacement is not or implements different interfaces, the proxy will need
* to be re-obtained or the old interfaces won't be supported and the new interface
* won't be implemented.
*
* @param a the advisor to replace
* @param b the advisor to replace it with
* @return whether it was replaced. If the advisor wasn't found in the
* list of advisors, this method returns {@code false} and does nothing.
* @throws AopConfigException in case of invalid advice
*/
boolean replaceAdvisor(Advisor a, Advisor b) throws AopConfigException;
/**
* Add the given AOP Alliance advice to the tail of the advice (interceptor) chain.
*
This will be wrapped in a DefaultPointcutAdvisor with a pointcut that always
* applies, and returned from the {@code getAdvisors()} method in this wrapped form.
*
Note that the given advice will apply to all invocations on the proxy,
* even to the {@code toString()} method! Use appropriate advice implementations
* or specify appropriate pointcuts to apply to a narrower set of methods.
*
* @param advice the advice to add to the tail of the chain
* @throws AopConfigException in case of invalid advice
* @see #addAdvice(int, Advice)
* @see DefaultPointcutAdvisor
*/
void addAdvice(Advice advice) throws AopConfigException;
/**
* Add the given AOP Alliance Advice at the specified position in the advice chain.
*
This will be wrapped in a {@link DefaultPointcutAdvisor}
* with a pointcut that always applies, and returned from the {@link #getAdvisors()}
* method in this wrapped form.
*
Note: The given advice will apply to all invocations on the proxy,
* even to the {@code toString()} method! Use appropriate advice implementations
* or specify appropriate pointcuts to apply to a narrower set of methods.
*
* @param pos index from 0 (head)
* @param advice the advice to add at the specified position in the advice chain
* @throws AopConfigException in case of invalid advice
*/
void addAdvice(int pos, Advice advice) throws AopConfigException;
/**
* Remove the Advisor containing the given advice.
*
* @param advice the advice to remove
* @return {@code true} of the advice was found and removed;
* {@code false} if there was no such advice
*/
boolean removeAdvice(Advice advice);
/**
* Return the index (from 0) of the given AOP Alliance Advice,
* or -1 if no such advice is an advice for this proxy.
*
The return value of this method can be used to index into
* the advisors array.
*
* @param advice the AOP Alliance advice to search for
* @return index from 0 of this advice, or -1 if there's no such advice
*/
int indexOf(Advice advice);
/**
* As {@code toString()} will normally be delegated to the target,
* this returns the equivalent for the AOP proxy.
*
* @return a string description of the proxy configuration
*/
String toProxyConfigString();
}