轉(zhuǎn)載自： http://chenjumin.iteye.com/blog/364948

?

一、基礎(chǔ)接口和類(lèi)

???? 1、Person接口的源碼

      public interface Person {
	public void info();
	public void show(String message);
}
    

?

???? 2、PersonImpl類(lèi)的源碼

      public class PersonImpl implements Person {
	private String name;
	private int age;
	
	public void setName(String name) {
		this.name = name;
	}

	public void setAge(int age) {
		this.age = age;
	}

	public void info() {
		System.out.println("\t我叫" + name + ",今年" + age + "歲。");
	}

	public void show(String message) {
		System.out.println(message);
	}
}

    

?

??? 3、bean的配置

      <!-- 目標(biāo)對(duì)象 -->
<bean id="personTarget" class="com.cjm.aop.PersonImpl">
	<property name="name" value="Raymond.chen"/>
	<property name="age" value="30"/>
</bean>

    

?

二、Spring AOP支持的通知類(lèi)型

???? 一）環(huán)繞通知（Around advice）

????????? 實(shí)現(xiàn)環(huán)繞通知需要實(shí)現(xiàn)org.aopalliance.intercept.MethodInterceptor接口。

?????????????? 1、PersonAroundAdvice類(lèi)的源碼

      public class PersonAroundAdvice implements MethodInterceptor {
	public Object invoke(MethodInvocation invocation) throws Throwable {
		System.out.println("AroundAdvice：方法調(diào)用前");
		
		//不要忘記調(diào)用invocation的proceed方法哦
		Object result = invocation.proceed(); 
		
		System.out.println("AroundAdvice：方法調(diào)用后");
		return result;
	}
}

    

?

?????????????? 2、bean配置

      <bean id="personAroundAdvice" class="com.cjm.aop.PersonAroundAdvice"/>

<!-- 代理工廠bean -->
<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personAroundAdvice</value>
		</list>
	</property>
</bean>

    

?

?????????????? 3、測(cè)試代碼

      ApplicationContext context = new FileSystemXmlApplicationContext("classpath:com/cjm/aop/beans.xml");
Person p = (Person)context.getBean("person");  //注意這里是代理工廠Bean的ID
p.info();

    

?

???? 二）前置通知（Before advice）

????????? 實(shí)現(xiàn)前置通知需要實(shí)現(xiàn)org.springframework.aop.MethodBeforeAdvice接口。

?????????????? 1、PersonBeforeAdvice類(lèi)的源碼

      public class PersonBeforeAdvice implements MethodBeforeAdvice {
	public void before(Method method, Object[] args, Object target) throws Throwable {
		System.out.println("BeforeAdvice：方法調(diào)用前");
	}
}

    

?

?????????????? 2、bean配置

      <bean id="personBeforeAdvice" class="com.cjm.aop.PersonBeforeAdvice"/>

<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personBeforeAdvice</value>
		</list>
	</property>
</bean>

    

?

???? 三）返回后通知（After Returning advice）

????????? 實(shí)現(xiàn)返回后通知需要實(shí)現(xiàn)org.springframework.aop.AfterReturningAdvice接口。

?????????????? 1、PersonAfterReturningAdvice類(lèi)的源碼

      public class PersonAfterReturningAdvice implements AfterReturningAdvice {
	public void afterReturning(Object returnValue, Method method, Object[] args, Object target) throws Throwable {
		System.out.println("AfterReturningAdvice：方法調(diào)用后");
	}
}

    

?

?????????????? 2、bean配置

      <bean id="personAfterReturningAdvice" class="com.cjm.aop.PersonAfterReturningAdvice"/>

<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personAfterReturningAdvice</value>
		</list>
	</property>
</bean>

    

?

?????????????? 3、以上的配置中，通知對(duì)目標(biāo)對(duì)象的所有方法都會(huì)起作用。如果需要過(guò)濾掉一部分方法，可以用正則表達(dá)式切入點(diǎn)配置器或者方法名匹配切入點(diǎn)配置器實(shí)現(xiàn)。

      <!-- 通知與正則表達(dá)式切入點(diǎn)一起配置 -->
<!-- Advisor等于切入點(diǎn)加通知 -->
<!-- 方法名匹配切入點(diǎn)配置器：org.springframework.aop.support.NameMatchMethodPointcutAdvisor -->
<bean id="personPointcutAdvisor" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
	<property name="advice" ref="personAfterReturningAdvice"/>
	<property name="patterns">
		<list>
			<value>.*info.*</value>
		</list>
	</property>
</bean>

<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personPointcutAdvisor</value>
		</list>
	</property>
</bean>

    

?

???? 四）異常通知（Throws advice）

????????? 當(dāng)連接點(diǎn)拋出異常時(shí)，異常通知被調(diào)用。實(shí)現(xiàn)異常通知需要實(shí)現(xiàn)org.springframework.aop.ThrowsAdvice接口，該接口不包含任何方法，但在實(shí)現(xiàn)該接口時(shí)必須實(shí)現(xiàn)如下形式的方法：
???????????????? afterThrowing([Method], [args], [target], Throwable subclass)
????????? 可以實(shí)現(xiàn)一個(gè)或多個(gè)這樣的方法。在這些方法中，只有第四個(gè)參數(shù)是必需的，前三個(gè)參數(shù)可選。

?

????????? 1、PersonThrowsAdvice類(lèi)的源碼

      public class PersonThrowsAdvice implements ThrowsAdvice {
	public void afterThrowing(FileNotFoundException ex){
		System.out.println("ThrowsAdvice >> FileNotFoundException：" + ex.toString());
	}

	public void afterThrowing(Object[] args, Exception ex){
		System.out.println("ThrowsAdvice >> Exception：" + ex.getMessage());
	}

	public void afterThrowing(Method method, Object[] args, Object target, Throwable ex){
		System.out.println("ThrowsAdvice >> Throwable：" + ex.getMessage());
	}
}

    

?

??????????2、bean配置

      <bean id="personThrowsAdvice" class="com.cjm.aop.PersonThrowsAdvice"/>

<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personThrowsAdvice</value>
		</list>
	</property>
</bean>

    

?

???? 五）引入通知（Introduction advice）

?????????? 引入通知是一種特殊的通知，它能將新的成員變量、成員方法引入到目標(biāo)類(lèi)中。它不能作用于任何切入點(diǎn)，因?yàn)樗蛔饔糜陬?lèi)層次，而不是方法層次。實(shí)現(xiàn)引入通知需要實(shí)現(xiàn)IntroductionAdvisor和IntroductionInterceptor接口。

?????????? 引入通知不能調(diào)用proceed方法。Advisor必須針對(duì)每個(gè)實(shí)例，并且是有狀態(tài)的。

?????????? 引入通知的效果類(lèi)似于設(shè)計(jì)模式中的訪問(wèn)者模式（Visitor Pattern）。

?

?

???????????1、Lockable接口的源碼

      public interface Lockable {
	void lock();
	void unlock();
	boolean locked();
}

    

?

?????????? 2、LockableImpl類(lèi)的源碼

      public class LockableImpl extends DelegatingIntroductionInterceptor implements Lockable {
	private boolean locked;
	
	public void lock() {
		this.locked = true;
	}

	public void unlock() {
		this.locked = false;
	}

	public boolean locked() {
		return this.locked;
	}

	@Override
	public Object invoke(MethodInvocation invocation) throws Throwable {
		if(this.locked){
			throw new RuntimeException("加鎖，無(wú)法執(zhí)行");
		}
		
		//這里不能調(diào)用invocation的proceed方法
		//通常不需要改寫(xiě)invoke方法，直接調(diào)用父類(lèi)的該方法即可
		return super.invoke(invocation);
	}
}

    

?

?????????? 3、PersonIntroductionAdvice類(lèi)的源碼

      public class PersonIntroductionAdvice extends DefaultIntroductionAdvisor {
	public PersonIntroductionAdvice(){
		super(new LockableImpl(), Lockable.class);
	}
}

    

?

?????????? 4、bean配置

      <!-- Advice必須針對(duì)每個(gè)實(shí)例，所以scope要設(shè)為prototype -->
<bean id="personIntroductionAdvice" class="com.cjm.aop.introduction.PersonIntroductionAdvice" scope="prototype"/>

<bean id="person" class="org.springframework.aop.framework.ProxyFactoryBean">
	<property name="proxyInterfaces" value="com.cjm.aop.Person"/>
	<property name="target" ref="personTarget"/>
	<property name="interceptorNames">
		<list>
			<value>personIntroductionAdvice</value>
		</list>
	</property>
</bean>

    

?

?????????? 5、測(cè)試代碼