02.Spring5.x Aop

第一章：Spring AOP

Aop面向切面编程

1. 新建一个空的 Java maven项目，命名为【spring01】

2. 修改pom.xml文件，增加如下依赖

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>

        <spring.version>5.2.5.RELEASE</spring.version>
        <aopalliance.version>1.0</aopalliance.version>
        <aspectj.weaver>1.9.2</aspectj.weaver>
    </properties>

    <dependencies>
        <!-- spring -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
        </dependency>


        <!--切入点表达式的支持-->
        <dependency>
            <groupId> org.aspectj</groupId>
            <artifactId> aspectjweaver</artifactId>
            <version>1.6.11</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>RELEASE</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>com.aliyun</groupId>
            <artifactId>aliyun-java-sdk-core</artifactId>
            <version>4.5.3</version>
        </dependency>
    </dependencies>

3.创建通知类

public class MyAspject {

    public void before() {
        System.out.println("前置通知");
    }
    public Object around(ProceedingJoinPoint j) {

        Object proceed = null;
        try {
            System.out.println("前置通知");
            proceed = j.proceed();
            System.out.println("后置通知");
            return proceed;
        } catch (Throwable throwable) {
            System.out.println("异常通知");
            throwable.printStackTrace();
        }finally{
            System.out.println("最终通知");
        }
        return proceed;
    }

}

4.创建applicationContext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:tx="http://www.springframework.org/schema/tx"
       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
       https://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">

    <bean id="userDao" class="club.gskj.dao.impl.UserDaoImpl"></bean>
    <bean id="aspject" class="club.gskj.aspject.MyAspject"></bean>

<!--配置 切面-->
<aop:config>
    <!--切入点表达式-->
    <aop:pointcut id="point" expression="execution(* club.gskj.dao..*.*(..))"/>
    <!--切入点-->
    <aop:aspect ref="aspject">
        <aop:before method="before" pointcut-ref="point"/>
        <aop:around method="around" pointcut-ref="point" arg-names="j"/>
    </aop:aspect>
</aop:config>

</beans>

5.测试类

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:applicationContext.xml")
public class AspectTest {

    @Autowired
    UserDao userDao;

    @Test
    public void teset1() {
        userDao.add();
    }
}

Aop面向切面编程，anno注解模式

1. 通知类

@Aspect
@Component
public class MyAspject2 {

    @Pointcut(value = "execution(* club.gskj.dao..*.*(..)))")
    public void pointCut() {
    }

    @Before(value = "pointCut()")
    public void before() {
        System.out.println("前置通知");
    }

    @Around(value = "pointCut()")
    public Object around(ProceedingJoinPoint j) {

        Object proceed = null;
        try {
            System.out.println("前置通知 anno");
            proceed = j.proceed();
            System.out.println("后置通知 anno");
            return proceed;
        } catch (Throwable throwable) {
            System.out.println("异常通知 anno");
            throwable.printStackTrace();
        } finally {
            System.out.println("最终通知 anno");
        }
        return proceed;
    }
}

2. applicationContext配置

<?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:tx="http://www.springframework.org/schema/tx"
       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
       https://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">

    <bean id="userDao" class="club.gskj.dao.impl.UserDaoImpl"></bean>
    <bean id="aspject" class="club.gskj.aspject.MyAspject"></bean>


    <!--开启 aop 自动注解-->
    <aop:aspectj-autoproxy/>
    <!--开启扫描包-->
    <context:component-scan base-package="club.gskj"/>
</beans>

3.测试类测试

• 总结：

• aop面向切面编程。重点在于使用的是 动态代理模式。在不改变源代码的基础上，对方法进心再次加强