spring aop

pom.xml

<dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>1.8.13</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.13</version>
        </dependency>

Hello

package org.mythsky.springaopdemo;

public interface Hello {
    // 定义一个简单方法，模拟应用中的业务逻辑方法
    void foo();
    // 定义一个addUser()方法，模拟应用中的添加用户的方法
    int addUser(String name , String pass);
}

HelloImpl

package org.mythsky.springaopdemo;

import org.aspectj.lang.annotation.Pointcut;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Component;

@Component("hello")
public class HelloImpl implements Hello {

    public void foo() {
        System.out.println("执行Hello组件的foo()方法");
    }

    public int addUser(String name, String pass) {
        System.out.println("执行Hello组件的addUser添加用户："+name);
        return 0;
    }
}

AuthAspect

package org.mythsky.springaopdemo;

import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class AuthAspect {
    @Before("execution(* org.mythsky.springaopdemo.*.*(..))")
    public void authority(){
        System.out.println("模拟执行权限检查");
    }
}

services.xml

<context:component-scan base-package="org.mythsky.springaopdemo"></context:component-scan>
    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>

BeanTest

package org.mythsky.springaopdemo;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class BeanTest {
    public static void main(String[] args){
        ApplicationContext ctx=new ClassPathXmlApplicationContext("services.xml");
        Hello hello = ctx.getBean("hello" , Hello.class);
        hello.foo();
        hello.addUser("孙悟空" , "7788");
    }
}

运行结果：

这里要注意切面类也需要添加@Component注解。

 AfterReturning

LogAspect

package org.mythsky.springaopdemo;

import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class LogAspect {
    @AfterReturning(returning = "rvt",pointcut = "execution(* org.mythsky.springaopdemo.*.*(..))")
    public void log(Object rvt){
        System.out.println("获取目标方法返回值:"+rvt);
        System.out.println("模拟记录日志功能...");
    }
}

重新运行结果：

 AfterThrowing

RepairAspect

package org.mythsky.springaopdemo;

import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class RepairAspect {
    @AfterThrowing(throwing = "ex",pointcut = "execution(* org.mythsky.springaopdemo.*.*(..))")
    public void doRecoveryActions(Throwable ex){
        System.out.println("目标方法中抛出的异常:"+ex);
        System.out.println("模拟Advice对异常的修复...");
    }
}

修改下HelloImpl

public int addUser(String name, String pass) {
        System.out.println("执行Hello组件的addUser添加用户："+name);
        if(name.length()<3||name.length()>10){
            throw new IllegalArgumentException("name参数的长度必须大于3，小于10！");
        }
        return 18;
    }

修改主程序BeanTest

public static void main(String[] args){
        ApplicationContext ctx=new ClassPathXmlApplicationContext("services.xml");
        Hello hello = ctx.getBean("hello" , Hello.class);
        hello.foo();
        hello.addUser("悟空" , "7788");
    }

运行结果：

 After

ReleaseAspect

package org.mythsky.springaopdemo;

import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class ReleaseAspect {
    @After("execution(* org.mythsky.springaopdemo.*.*(..))")
    public void release(){
        System.out.println("模拟方法结束后的释放资源...");
    }
}

运行结果：

 Around

TxAspect

package org.mythsky.springaopdemo;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class TxAspect {
    @Around("execution(* org.mythsky.springaopdemo.*.*(..))")
    public Object processTx(ProceedingJoinPoint jp) throws Throwable {
        System.out.println("执行目标方法之前，模拟开始事务...");
        Object[] args=jp.getArgs();
        if(args!=null&&args.length>1){
            args[0]="【增加的前缀】"+args[0];
        }
        Object rvt=jp.proceed(args);
        System.out.println("执行目标方法之后，模拟结束事务...");
        if(rvt!=null&&rvt instanceof Integer)
            rvt=(Integer)rvt*(Integer)rvt;
        return rvt;
    }
}

运行结果：