Java面向切面编程AOP怎么实现-创新互联

这篇文章主要介绍“Java面向切面编程AOP怎么实现”，在日常操作中，相信很多人在Java面向切面编程AOP怎么实现问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答”Java面向切面编程AOP怎么实现”的疑惑有所帮助！接下来，请跟着小编一起来学习吧！

一：背景
Spring的AOP的存在目的是为了解耦。AOP可以让一组类共享相同的行为。在OOP中只能通过继承类和实现接口，来是代码的耦合度增强，且类继承只能为单继承，阻碍更多行为添加到一组类上，AOP弥补了OPP的不足。

二：概述  Spring支持AspectJ的注解方式切面编程

1.使用@Aspect 声明一个切面。

2.使用@After,@Before,@Around 定义建言（advice）,可直接将拦截规则（切点）作为参数。

3.其中@After,@Before,@Around参数的拦截规则为切点（PointCut） ,为了使切点复用，可使用@PointCut 专门定义拦截规则，然后在@After,@Before,@Around的参数中调用。

4.其中符合条件的每一个被拦截处为连接点（JoinPoint）

三：代码实例

1.pom.xml

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2.             org.springframework

3.             spring-core

4.         

5.         

6.             org.springframework

7.             spring-beans

8.         

10.         

11.             org.springframework

12.             spring-context

13.         

15.         

16.             org.springframework

17.             spring-aop

18.         

20.         

21.             org.aspectj

22.             aspectjrt

23.         

25.         

26.             org.aspectj

27.             aspectjweaver

28.         

2.拦截规则的注解

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1. @Target(ElementType.METHOD)

2. @Retention(RetentionPolicy.RUNTIME)

3. @Documented

4. public @interface Action {

5.     String name();

6. }

2.注解的被拦截类

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1. @Service

2. public class DemoAnnotationService {

4.     @Action(name = "注解式拦截的add操作")

5.     public void add() {

6.        System.out.println("======DemoAnnotationService方法add()=========");

7.     }

8. }

3.方法规则被拦截类

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1. @Service

2. public class DemoMethodService {

3.     public String add() throws Exception{

4.         System.out.println("======DemoMethodService方法add()=========");

5.         int i=100/0;

6.         return "SUCCESS";

7.     }

8. }

4.编写切面

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1. @Aspect

2. @Component

3. public class LogAspect {

5.     @Pointcut("@annotation(com.gemdale.gmap.spring.boot.demo.Action)")

6.     public void annotationPointCut() {

7.     }

9.     @After("annotationPointCut()")

10.     public void after(JoinPoint joinPoint) {

11.         MethodSignature signature = (MethodSignature) joinPoint.getSignature();

12.         Method method = signature.getMethod();

13.         Action action = method.getAnnotation(Action.class);

15.         System.out.println("注解式拦截 " + action.name());

16.     }

18.     @Before("execution(* com.gemdale.gmap.spring.boot.demo.DemoMethodService.*(..))")

19.     public void methodBefore(JoinPoint joinPoint) {

20.         MethodSignature signature = (MethodSignature) joinPoint.getSignature();

21.         Method method = signature.getMethod();

22.         System.out.println("before方法规则式拦截 " + method.getName());

23.     }

25.     @After("execution(* com.gemdale.gmap.spring.boot.demo.DemoMethodService.*(..))")

26.     public void methodAfter(JoinPoint joinPoint) {

27.         MethodSignature signature = (MethodSignature) joinPoint.getSignature();

28.         Method method = signature.getMethod();

29.         System.out.println("after方法规则式拦截 " + method.getName());

30.     }

32.     @AfterReturning(pointcut = "execution(* com.gemdale.gmap.spring.boot.demo.DemoMethodService.*(..))", returning = "result")

33.     public void methodAfterResult(JoinPoint joinPoint, Object result) {

34.         MethodSignature signature = (MethodSignature) joinPoint.getSignature();

35.         Method method = signature.getMethod();

36.         System.out.println("after result方法规则式拦截 " + method.getName() + "result=" + result);

37.     }

39.     @AfterThrowing(pointcut = "execution(* com.gemdale.gmap.spring.boot.demo.DemoMethodService.*(..))", throwing = "e")

40.     public void methodAfterException(JoinPoint joinPoint, Exception e) {

41.         MethodSignature signature = (MethodSignature) joinPoint.getSignature();

42.         Method method = signature.getMethod();

43.         System.out.println("after exception方法规则式拦截 " + method.getName() + " e=" + e.getMessage());

44.     }

46. }

5.配置类

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1. @Configuration

2. @ComponentScan("com.gemdale")

3. @EnableAspectJAutoProxy

4. public class AppliactionConfig {

6. }

6.执行类

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1. public class Start {

2.     public static void main(String[] args) throws Exception{

4.         AnnotationConfigApplicationContext configApplicationContext = new AnnotationConfigApplicationContext(

5.                 AppliactionConfig.class);

6.         // UseFunctionService

7.         // useFunctionService=configApplicationContext.getBean(UseFunctionService.class);

8.         // System.out.println(useFunctionService.sayHello("Gengchong"));

9.         DemoAnnotationService demoAnnotationService = configApplicationContext.getBean(DemoAnnotationService.class);

10.         DemoMethodService demoMethodService = configApplicationContext.getBean(DemoMethodService.class);

12.         demoAnnotationService.add();

14.         demoMethodService.add();

16.         configApplicationContext.close();

17.     }

18. }

到此，关于“Java面向切面编程AOP怎么实现”的学习就结束了，希望能够解决大家的疑惑。理论与实践的搭配能更好的帮助大家学习，快去试试吧！若想继续学习更多相关知识，请继续关注创新互联-成都网站建设公司网站，小编会继续努力为大家带来更多实用的文章！