Spring AOP

1. 导入pom配置

<dependency>
    <groupId>org.aspectj</groupId>
    <artifactId>aspectjweaver</artifactId>
    <version>1.9.6</version>
</dependency>

2. applicationContext.xml配置

    <!--导入bean对象-->
    <bean id="userDao" class="com.c21w.dao.impl.UserDaoImpl"></bean>
    <bean id="after" class="com.c21w.dao.aop.After"></bean>
    <bean id="before" class="com.c21w.dao.aop.Before"></bean>

    <!--配置约束-->
    <aop:config>
        <!--设置切入点-->
        <aop:pointcut id="point" expression="execution(* com.c21w.dao.impl.UserDaoImpl.*(..))"/>

        <!--设置执行环绕-->
        <aop:advisor advice-ref="after" pointcut-ref="point"></aop:advisor>
        <aop:advisor advice-ref="before" pointcut-ref="point"></aop:advisor>
    </aop:config>

import org.springframework.aop.MethodBeforeAdvice;
import java.lang.reflect.Method;

//方法执行前调用
public class Before implements MethodBeforeAdvice {
    @Override
    public void before(Method method, Object[] objects, Object o) throws Throwable {
        System.out.println(o.getClass().getName() + "准备执行" + method.getName() + "方法");
    }
}
//========================================================================================================
import org.springframework.aop.AfterReturningAdvice;
import java.lang.reflect.Method;

//方法执行之后调用
public class After implements AfterReturningAdvice {
    @Override
    public void afterReturning(Object o, Method method, Object[] objects, Object o1) throws Throwable {
        System.out.println(o1.getClass().getName() + "执行了" + method.getName() + "方法并且返回值是" + o);
    }
}

或使用自定义增强类

    <!--导入bean对象-->
    <bean id="userDao" class="com.c21w.dao.impl.UserDaoImpl"></bean>

    <!--增强类-->
    <bean id="proxy" class="com.c21w.dao.aop2.Proxy"></bean>

    <!--配置约束-->
    <aop:config>
        <!--自定义切面-->
        <aop:aspect ref="proxy">
            <!--切入点-->
            <aop:pointcut id="point" expression="execution(* com.c21w.dao.impl.UserDaoImpl.*(..))"/>
            <!--通知(切入的位置和方法)-->
            <aop:after method="after" pointcut-ref="point"></aop:after>
            <aop:before method="before" pointcut-ref="point"></aop:before>
        </aop:aspect>
    </aop:config>

public class Proxy {
    public void after(){
        System.out.println("执行了after方法");
    }
    public void before(){
        System.out.println("执行了before方法");
    }
}

注解实现

    <!--导入bean对象-->
    <bean id="userDao" class="com.c21w.dao.impl.UserDaoImpl"></bean>

    <!--开启注解支持-->
    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>
    <!--导入注解对象-->
    <bean id="ann" class="com.c21w.dao.aop3.AnnotationProxy"></bean>

import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;


// 标注这个类是一个切面
@Aspect
public class AnnotationProxy {

    // 设置切入点
    @After("execution(* com.c21w.dao.impl.UserDaoImpl.*(..))")
    public void after(){
        System.out.println("========after=======");
    }

    // 设置切入点
    @Before("execution(* com.c21w.dao.impl.UserDaoImpl.*(..))")
    public void before(){
        System.out.println("=======before=======");
    }
}