@AspectJ註解方式的aop

第一步：匯入依賴

 <dependencies>
​
​
    <!-- 引入spring 依賴 作為CGLIB的依賴 -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>5.3.12</version>
    </dependency>
​
    <!-- aspect  -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aspects</artifactId>
      <version>5.3.12</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-log4j12 -->
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-log4j12</artifactId>
      <version>1.7.25</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
      <scope>compile</scope>
    </dependency>
    <!--spring 整合測試-->
     <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>5.3.7</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
​
 

第二步：開啟@aspect註冊 和包掃描

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/aop
    http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
​
​
  <!--使用bean 註解掃描 自動開啟註解功能
   *就是如果某個類上面帶有特定的註解
   @Component，@Repository，@Service，@Controller 就會將這個物件作為bean注入到spring容器中
  -->
  <context:component-scan base-package="com.bird"/>
​
  <!--  配置aop的aspectj的自動代理：
    *自動掃描bean元件中，含有@Aspect的bean 將其作為aop管理 開啟自動代理
  -->
  <aop:aspectj-autoproxy/>
​
</beans>
 

第三步：定義目標物件並注入到spring容器中

public interface ICustomerService {
  public void save();
  public int find();
  public int error();
}
@Component
public class ICustomerServiceImpl implements ICustomerService {
  public void save() {
    System.out.println("客戶儲存了。。。。。");
   }
​
  public int find() {
    System.out.println("客戶查詢數量了。。。。。");
    return 100;
   }
​
  @Override
  public int error() {
    int a = 1 / 0;
    return 0;
   }
}
=======上面是基於介面的動態代理========下面是基於類的動態代理=========
@Service
public class ProductService {
  public void save() {
    System.out.println("商品儲存了。。。。。");
   }
​
  public int find() {
    System.out.println("商品查詢數量了。。。。。");
    return 99;
   }
}
​
 

第四步：編寫通知類 並注入到spring容器中

package com.bird.advice.annotationaspectjaop.aspect;
​
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;
​
/**
 * @data 2021/11/28 10:03
 * @author: bird
 * @description: 這個是基於註解的方式定義的通知類
 */
@Component(value = "myAspect") // 將當前類注入到spring容器中
@Aspect //將該類標識為切面類（這裡面有方法進行增強），相當於<aop:aspect ref=”myAspect”> //宣告但前的這個類是通知類 專門用來增強
public class MyAspect {
​
  // 這個是基於介面的
  // 切入點：切入點就是攔截方法 意思就是要對哪些方法進行攔截 然後在通知裡面進行攔截
  @Pointcut(value = "execution(* com.bird.advice.annotationaspectjaop.targetobject.ICustomerServiceImpl.save(..))")
  public void myPointcut() {
   }
​
  // 這個是基於類 進行切入點的
  @Pointcut(value = "execution(* com.bird.advice.annotationaspectjaop.targetobject.ProductService.save(..))")
  public void mypointcut2() {
   }
​
  @Pointcut(value = "execution(* com.bird.advice.annotationaspectjaop.targetobject.ProductService.find(..))")
  public void myPointcut3() {
   }
​
  @Pointcut(value = "execution(* com.bird.advice.annotationaspectjaop.targetobject.ICustomerServiceImpl.find(..))")
  public void myPointcut4() {
   }
​
  @Pointcut(value = "execution(* com.bird.advice.annotationaspectjaop.targetobject.ICustomerServiceImpl.error(..))")
  public void myPointcut5() {
​
   }
​
​
  // 前置通知 在save方法執行之前 執行的方法
  @Before(value = "myPointcut()|| mypointcut2()")
  public void before(JoinPoint joinPoint) {
    System.out.println("=======前置通知。。。。。");
   }
​
​
  // 後置通知
  @AfterReturning(value = "myPointcut()|| mypointcut2()||myPointcut3()", returning = "returnVal")
  public Object afterReturning(JoinPoint joinPoint, Object returnVal) {
    System.out.println("++++++++後置通知+++++++++++++：結果" + returnVal);
    return returnVal;
   }
​
​
  // 環繞通知
  @Around(value = "myPointcut4()")
  public Object around(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
    System.out.println("環繞通知------前");
    Object proceed = proceedingJoinPoint.proceed();
    System.out.println("環繞通知------後");
    return proceed;
   }
​
  // 丟擲通知  若目標方法執行時 丟擲了異常 那麼就會執行這個增強
  @AfterThrowing(value = "myPointcut5()", throwing = "ex")
  public void afterThrowing(JoinPoint joinPoint, Throwable ex) {
    StackTraceElement[] stackTrace = ex.getStackTrace();
    StackTraceElement stackTraceElement = stackTrace[0];
    System.out.println("---丟擲通知......------丟擲的資訊:" + ex.getMessage() + "具體的錯誤行：" + stackTraceElement);
   }
​
  // 最終通知 無論目標方法是否發生了異常都會執行下面的方法
  @After(value = "myPointcut5()")
  public void after(JoinPoint joinPoint) {
    System.out.println("--最終通知-----不管是否發生了異常----");
   }
​
}
​

第五步：測試

package com.bird.jdkproxy;
​
 import com.bird.advice.annotationaspectjaop.targetobject.ICustomerService;
 import com.bird.advice.annotationaspectjaop.targetobject.ProductService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
​
/**
 * @data 2021/11/28 10:21
 * @author: bird
 * @description: 這個是基於註解的方式實現的aop
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:applicationContext-annotation-aspect.xml") // 載入指定位置的bean
public class SpringAspectTest {
​
​
  @Autowired
  private ICustomerService customerService;
​
​
  @Autowired
  private ProductService productService;
​
  @Test
  public void test() {
    // 基於介面
    customerService.save();
    customerService.find();
    System.out.println("******************************************************");
    // 基於類
    productService.find();
    productService.save();
​
    System.out.println("%%%%%%%%%%%%%下面是丟擲異常通知%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%");
    customerService.error();
​
   }
}
​