註解實現的spring-aop

接口：

 1 package spring.aop;  2 
 3 public interface Arithmetic {  4 
 5  Integer add(Integer a,Integer b);  6  Integer sub(Integer a,Integer b);  7  Integer div(Integer a,Integer b);  8 
 9 
10 }

實現類：

 1 package spring.aop;  2 
 3 import org.springframework.stereotype.Component;  4 
 5 @Component  6 public class ArithmeticImpl implements Arithmetic{  7 
 8  @Override  9     public Integer add(Integer a, Integer b) { 10         System.out.println("add -> "+(a+b)); 11         return a+b; 12  } 13 
14  @Override 15     public Integer sub(Integer a, Integer b) { 16         System.out.println("sub -> "+(a-b)); 17         return a-b; 18  } 19 
20  @Override 21     public Integer div(Integer a, Integer b) { 22         System.out.println("div -> "+(a/b)); 23         return a/b; 24  } 25 
26 
27 }

配置文件：aop.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

    <!--


     -->

    <context:component-scan base-package="spring.aop"/>

    <!--自動爲匹配的類生成代理對象-->
    <aop:aspectj-autoproxy proxy-target-class="true" />

</beans>

驗證切面：

 1 package spring.aop;  2 
 3 import org.aspectj.lang.JoinPoint;  4 import org.aspectj.lang.annotation.Aspect;  5 import org.aspectj.lang.annotation.Before;  6 import org.springframework.core.annotation.Order;  7 import org.springframework.stereotype.Component;  8 
 9 import java.util.Arrays; 10 
11 @Order(1) 12 @Aspect 13 @Component 14 public class VliAspect { 15 
16     @Before("spring.aop.aspect.declareJointPointExpression()") 17     public void validateArgs(JoinPoint joinPoint){ 18 
19         System.out.println("validateArgs -> "+ Arrays.asList(joinPoint.getArgs())); 20  } 21 }

主切面

 1 package spring.aop;  2 
 3 import org.aspectj.lang.JoinPoint;  4 import org.aspectj.lang.annotation.*;  5 import org.springframework.core.annotation.Order;  6 import org.springframework.stereotype.Component;  7 
 8 import java.util.Arrays;  9 import java.util.List; 10 
11 //聲明這個切面的優先級，值越小，優先級越高
12 @Order(2) 13 //聲明這個類是一個切面
14 @Aspect 15 @Component 16 public class aspect { 17 
18     //定義一個方法，用於聲明切點表達式，通常該方法不寫其餘代碼
19     @Pointcut("execution( * spring.aop.*.*(*,*))") 20     public void declareJointPointExpression(){} 21 
22     //聲明該方法是一個前置通知
23     @Before("declareJointPointExpression()") 24     public void beforeMethod(JoinPoint joinPoint){ 25         String methodName = joinPoint.getSignature().getName(); 26         List<Object> args = Arrays.asList(joinPoint.getArgs()); 27         System.out.println("methodName:"+methodName+"--->before args: "+args); 28  } 29 
30 
31     //聲明該方法是一個後置通知,不管是否發生異常，都會在目標方法執行後執行 32     //後置通知沒法訪問目標方法的執行結果
33     @After("declareJointPointExpression()") 34     public void afterMethod(JoinPoint joinPoint){ 35         String methodName = joinPoint.getTarget().getClass().getName(); 36         List<Object> args = Arrays.asList(joinPoint.getArgs()); 37         System.out.println("methodName:"+methodName+"--->after args: "+args); 38  } 39 
40     //返回通知,目標方法正常結束後執行 41     //能夠訪問方法的返回值
42     @AfterReturning(value = "declareJointPointExpression()",returning = "result") 43     public void afterReturning(JoinPoint joinPoint,Object result){ 44         String methodName = joinPoint.getSignature().getName(); 45         System.out.println("methodName:"+methodName+"--->afterReturning args: "+result); 46 
47  } 48 
49     @AfterThrowing(value = "declareJointPointExpression())",throwing = "e") 50     public void afterThrowing(JoinPoint joinPoint,Exception e){ 51         String methodName = joinPoint.getSignature().getName(); 52         System.out.println("methodName:"+methodName+"--->afterThrowing args: "+e); 53 
54  } 55 }

測試類

package spring.aop; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class Main { public static void main(String[] args){ ApplicationContext ac = new ClassPathXmlApplicationContext("classpath:aop.xml"); Arithmetic proxy = ac.getBean("arithmeticImpl",ArithmeticImpl.class); proxy.add(3,5); System.out.println("-----------------------"); proxy.sub(3,0); System.out.println("-----------------------"); proxy.div(3,0); System.out.println("-----------------------"); } }

結果