基于注解开发AspectJ

红太狼 2022-04-13 14:25 303阅读 0赞

1.pom.xml,添加依赖

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
    
        <groupId>edu.njxz.demo</groupId>
        <artifactId>springTest</artifactId>
        <version>1.0-SNAPSHOT</version>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>5.0.6.RELEASE</version>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.12</version>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.47</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-jdbc</artifactId>
                <version>5.1.2.RELEASE</version>
            </dependency>
            <dependency>
                <groupId>commons-logging</groupId>
                <artifactId>commons-logging</artifactId>
                <version>1.2</version>
            </dependency>
            <dependency>
                <groupId>aopalliance</groupId>
                <artifactId>aopalliance</artifactId>
                <version>1.0</version>
            </dependency>
            <dependency>
                <groupId>org.aspectj</groupId>
                <artifactId>aspectjweaver</artifactId>
                <version>1.8.9</version>
            </dependency>
            <dependency>
                <groupId>org.aspectj</groupId>
                <artifactId>aspectjweaver</artifactId>
                <version>1.8.8</version>
            </dependency>
        </dependencies>
    
    
    </project>

2.创建目标类接口

public interface TestDao {
        void save();
        void delete();
    }

3.实现接口类

@Repository("testDao")
    public class TestDaoImpl  implements TestDao{
        public void save() {
            System.out.println("保存");
        }
    
        public void delete() {
            System.out.println("删除");
        }
    }

4.创建切面类，并进行注解

@Aspect  //对应<aop:aspect ref="myAspect">
    @Component  //对应<bean id="myAspect" class="">
    public class MyAspect {
    
        /**
         * 定义切入点  @Pointcut 相当于  <aop:pointcut id="myPointCut" expression="execution(* edu.njxz.demo.dynamicProxy.*.*(..))"></aop:pointcut>
         */
        @Pointcut("execution(* edu.njxz.demo.dynamicProxy.*.*(..))")
        private void myPointCut(){
    
        }
        /**
         * 前置通知，使用JoinPoint接口作为参数获得目标对象信息
         * @param jp
         */
        @Before("myPointCut()")
        public void before(JoinPoint jp){
            System.out.print("前置通知：模拟权限控制");
            System.out.println(",目标对象:"+jp.getTarget()+" ,被增强处理的方法："+jp.getSignature().getName());
        }
    
        /**
         * 后置返回通知
         * @param jp
         */
        @AfterReturning("myPointCut()")
        public void afterReturning(JoinPoint jp){
            System.out.print("后置返回通知：模拟删除临时文件");
            System.out.println(" ,被增强处理的方法："+jp.getSignature().getName());
        }
    
        /**
         * 环绕通知
         * @param pjp
         * @return
         * @throws Throwable
         * 必须throws Throwable
         */
        @Around("myPointCut()")
        public Object around(ProceedingJoinPoint pjp) throws Throwable{
            //开始
            System.out.println("环绕开始：执行目标方法前，模拟开启事务");
            //执行当前目标方法
            Object obj=pjp.proceed();
            //结束
            System.out.println("环绕结束：执行目标方法后，模拟关闭事务");
    
            return obj;
        }
    
        /**
         * 异常通知
         *
         */
    
        @AfterThrowing(value = "myPointCut()",throwing = "e")
        public void except(Throwable e){
            System.out.println("异常通知："+"程序执行异常"+e.getMessage());
        }
    
        /**
         * 后置通知，（最终通知）
         */
        @After("myPointCut()")
        public void after(){
            System.out.println("最终通知：模拟释放资源");
        }
    }

5.创建配置文件

<?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: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="edu.njxz.demo.aspectAnnotation"></context:component-scan>
        <context:component-scan base-package="edu.njxz.demo.dynamicProxy"></context:component-scan>
        
        <aop:aspectj-autoproxy></aop:aspectj-autoproxy>
    </beans>

6.测试运行

public class Test {
    
        public static void main(String[] args) {
            //把beans.xml的类加载到容器
            ApplicationContext applicationContext=new ClassPathXmlApplicationContext("app2.xml");
    
            //从容器中获取增强后的目标对象
            TestDao testDaoAdvice =(TestDao) applicationContext.getBean("testDao");
    
            //执行方法
            testDaoAdvice.save();
        }
    
    }