使用 Spring 实现 AOP

• 方式一：使用Spring的API接口 [主要SpringAPI接口实现]
• 方式二：自定义来实现AOP [主要是切面定义]
• 方式三：使用注解实现

1、使用AOP织入，需要首先导入一个依赖包

<!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver -->
<dependency>
    <groupId>org.aspectj</groupId>
    <artifactId>aspectjweaver</artifactId>
    <version>1.9.6</version>
</dependency>

2、代码测试

向原有业务中添加日志功能

1、编写UserService接口：

public interface UserService{
    public void add();
    public void delete();
    public void update();
    public void query();
}

2、编写UserServiceImpl接口实现类

//真实对象
public class UserServiceImpl implements UserService{
    public void add(){
        System.out.println("增加了一个用户！");
    }
    public void delete(){
        System.out.println("删除了一个用户！");
    }
    public void update(){
        System.out.println("修改了一个用户！");
    }
    public void query(){
        System.out.println("查询了一个用户！");
    }
}

3、编写Log日志类

添加方式一：使用Spring的API接口

public class BeforeLog implements MethodBeforeAdvice {
    //method:要执行的切入方法
    //args:参数
    //target:目标对象
    public void before(Method method, object[] args, object target) throws Throwable {
        System.out.print1n(target.getClass().getName()+"的"+method.getName()+"被执行了");
    }
}

public class AfterLog implements AfterReturningAdvice {
    //returnValue：返问值
    public void afterReturning(object returnValue, Method method, Object[] args, object target) throws Throwable {
        System.out.print1n("执行了"+method.getName ()+ "返回结果为: " +returnValue); 
    }
}

添加方式二：使用自定义diy类来实现aop

public class DiyPointCut {
    public void before(){
    	System.out.printn("=======方法执行前=======");
    }
    public void after(){
    	System.out.println("======方法执行后=======");
    }
}

添加方式三：使用注解实现

@Aspect //标注这个类是一个切面
public class AnnotationPointCut {
    @Before("execution(* com.qilu.service.UserServiceImpl.*(..))")
    public void before(){
    	System.out.println("====方法执行前=====");
    }
    
    @After("execution(* com.qilu.service.UserServiceImpl.*(..))")
    public void after(){
    	System.out.println("====方法执行后=====");
    }
    
    //在环绕增强中，我们可以给定一个参数，代表我们要获取处理切入的点
    @Around("execution(* com.qilu.service.UserServiceImpl.*(..))")
    public void around(ProceedingJoinPoint jp){
        System.out.println("执行前");
        //执行方法
	Object proceed = jp.proceed();
	System.out.println("执行后");
    }
}

4、向applicationContext.xml容器中注入bean，并配置aop

方式一：

<?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:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">

    <!-- 注册bean -->
    <bean id="userService" class="com.qilu.service.UserServiceImpl" />
    <bean id="beforelog" class="com.qilu.log.BeforeLog" />
    <bean id="afterlog" class="com.qilu.log.AfterLog" />

    <!-- 方式一：使用原生Spring API接口 -->
    <!-- 配置aop：需要导入aop约束 -->
    <aop:config>
    	<!-- 切入点 -->
        <aop:pointcut id="pointcut" expression="execution(* com.qilu.service.UserServiceImpl.*(..))" />
        
        <!-- 执行环绕增强 -->
        <aop:advisor advice-ref="beforelog" pointcut-ref="pointcut" />
        <aop:advisor advice-ref="afterlog" pointcut-ref="pointcut" />
    </aop:config>
</beans>

方式二：

<?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:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">

    <!-- 注册bean -->
    <bean id="userService" class="com.qilu.service.UserServiceImpl" />
    
    <!-- 方式二：自定义类 -->
    <bean id ="diy" class="com.qilu.DiyPointCut" />

    <aop:config>
        <!-- 自定义切面，ref 要引用的类 -->
    	<aop:aspect ref="diy">
        	<!-- 切入点 -->
        	<aop:pointcut id="pointcut" expression="execution(* com.qilu.service.UserServiceImpl.*(..))" />
            <!-- 通知 -->
            <aop:before method="before" pointcut-ref="pointcut" />
            <aop:after method="after" pointcut-ref="pointcut" />
        </aop:aspect>
    </aop:config>
   
</beans>

方式三：

<?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:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">

    <!-- 注册bean -->
    <bean id="userService" class="com.qilu.service.UserServiceImpl" />
    
    
    <!-- 方式三:使用注解 -->
    <bean id="annotationPointCut" class="com.qilu.log.annotationPointCut" />
	<!--开启注解支持! JDK(默认 proxy-target-class="false")   cglib(proxy-target-class="true") -->
	<aop:aspectj-autoproxy proxy-target-class="true"/>

   
</beans>

5、编写测试类

public class MyTest {
    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXml1App1icationContext("applicationContext.xml");
        //动态代理代理的是接口
        UserService userService = (UserService) context.getBean("userService");
        userService.add();
    }
}

使用 Spring 实现 AOP

原文地址：https://www.cnblogs.com/abc991314/p/13416061.html