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Spring-AOP 静态普通方法名匹配切面操作

2024-04-02 19:55

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概述

StaticMethodMatcherPointcutAdvisor代表一个静态方法匹配切面，它通过StaticMethodMatcherPointcut来定义切点，并通过类过滤和方法名来匹配所定义的切点.

实例

代码已托管到Github—> https://github.com/yangshangwei/SpringMaster

我们假设我们业务类中 Waiter和 Seller中都有同名的greetTo()方法.

业务类Waiter


package com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor;
public class Waiter {
	
	public void greetTo(String name) {
		System.out.println("Waiter Greet to " + name);
	}
	
	public void serverTo(String name) {
		System.out.println("Waiter Server to " + name);
	}
}

业务类Seller


package com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor;
public class Seller {
 
 public void greetTo(String name) {
  System.out.println("Seller Greet to " + name);
 }
}

现在我们希望通过StaticMethodMatcherPointcutAdvisor定义一个切面，在Waiter#greetTo()方法调用前织入一个增强，即连接点为Waiter#greetTo()方法调用前的位置。

切面代码


package com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor;
import java.lang.reflect.Method;
import org.springframework.aop.ClassFilter;
import org.springframework.aop.support.StaticMethodMatcherPointcutAdvisor;

public class GreetingAdvisor extends StaticMethodMatcherPointcutAdvisor {
	private static final long serialVersionUID = 1L;
	
	@Override
	public boolean matches(Method method, Class<?> targetClass) {
		return "greetTo".equals(method.getName());
	}
	
	public ClassFilter getClassFilter() {
		return new ClassFilter() {
			@Override
			public boolean matches(Class<?> clazz) {
				return Waiter.class.isAssignableFrom(clazz);
			}
		};
	}
}

StaticMethodMatcherPointcutAdvisor 抽象类唯一需要定义的是matches（）方法，在默认情况下，该切面匹配所有的类，这里通过覆盖getClassFilter（）方法，让它仅匹配Waiter类及其子类。

当然，Advisor还需要一个增强类的配合 .

我们来定义一个前置增强


package com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor;
import java.lang.reflect.Method;
import org.springframework.aop.MethodBeforeAdvice;

public class GreetBeforeAdivce implements MethodBeforeAdvice {
	@Override
	public void before(Method method, Object[] args, Object target)
			throws Throwable {
		// 输出切点
		System.out.println("Pointcut:" + target.getClass().getName() + "."
				+ method.getName());
		String clientName = (String) args[0];
		System.out.println("How are you " + clientName + " ?");
	}
}

我们使用Spring配置来定义切面等信息


<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:p="http://www.springframework.org/schema/p"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
	
	<!-- 配置切面：静态方法匹配切面 -->
	
	<!-- Waiter目标类 -->
	<bean id="waiterTarget" class="com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor.Waiter"/>
	<!-- Seller目标类 -->
	<bean id="sellerTarget" class="com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor.Seller"/>
	
	<!-- 前置增强 -->
	<bean id="greetBeforeAdvice" class="com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor.GreetBeforeAdivce"/>
	
	<!-- 切面 -->
	<bean id="greetAdvicesor" class="com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor.GreetingAdvisor"
		p:advice-ref="greetBeforeAdvice"/> <!-- 向切面注入一个前置增强 -->
		
	<!-- 通过父bean,配置公共的信息 -->
	<bean id="parent" abstract="true"  
		class="org.springframework.aop.framework.ProxyFactoryBean"
		p:interceptorNames="greetAdvicesor"
		p:proxyTargetClass="true"/>
	<!-- waiter代理 -->
	<bean id="waiter" parent="parent" p:target-ref="waiterTarget"/>
	<!-- seller代理 -->
	<bean id="seller" parent="parent" p:target-ref="sellerTarget"/>
	
</beans>

单元测试类


package com.xgj.aop.spring.advisor.StaticMethodMatcherPointcutAdvisor;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class StaticMethodMatcherPointcutAdvisorTest {
	@Test
	public void test() {
		// 加载配置文件,启动容器
		ApplicationContext ctx = new ClassPathXmlApplicationContext(
				"classpath:com/xgj/aop/spring/advisor/StaticMethodMatcherPointcutAdvisor/conf-advisor.xml");
		// 从容器中获取Bean
		Waiter waiter = ctx.getBean("waiter", Waiter.class);
		Seller seller = ctx.getBean("seller", Seller.class);
		// 调用业务方法
		waiter.greetTo("XiaoGongJiang");
		waiter.serverTo("XiaoGongJiang");
		seller.greetTo("XiaoGongJiang");
	}
}

运行结果：

这里写图片描述