Spring 之AOP 详解

Posted 2020-09-14

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第一节：AOP 简介

AOP 简介：百度百科；

面向切面编程(也叫面向方面编程)：Aspect Oriented Programming(AOP)，是软件开发中的一个热点，也是Spring框架中的一个重要内容。利用AOP 可以对业务逻辑的各个部分进行隔离，从而使得业务逻辑各部分之间的耦合度降低，提高程序的可重用性，同时提高了开发的效率。

主要的功能是：日志记录，性能统计，安全控制，事务处理，异常处理等等。

--------

这里我先开头讲一个例子代码程序：

T.java：

 1 package com.wishwzp.test;
 2 
 3 import org.junit.Before;
 4 import org.junit.Test;
 5 import org.springframework.context.ApplicationContext;
 6 import org.springframework.context.support.ClassPathXmlApplicationContext;
 7 
 8 import com.wishwzp.service.StudentService;
 9 
10 
11 public class T {
12 
13     private ApplicationContext ac;
14 
15     @Before
16     public void setUp() throws Exception {
17         ac=new ClassPathXmlApplicationContext("beans.xml");
18     }
19 
20     @Test
21     public void test1() {
22         StudentService studentService=(StudentService)ac.getBean("studentService");
23         studentService.addStudent("张三");
24     }
25     
26 
27 }

beans.xml:

1 <?xml version="1.0" encoding="UTF-8"?>
2 <beans xmlns="http://www.springframework.org/schema/beans"
3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4     xsi:schemaLocation="http://www.springframework.org/schema/beans
5         http://www.springframework.org/schema/beans/spring-beans.xsd">
6     
7     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
8     
9 </beans>

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public void addStudent(String name) {
 9         System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         System.out.println("完成学生"+name+"的添加");
12     }
13 
14 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public void addStudent(String name);
6 }

运行结果显示：

开始添加学生张三
添加学生张三
完成学生张三的添加

--------------

第二节：Spring AOP 实例

1，前置通知；

2，后置通知；

3，环绕通知；

4，返回通知；

5，异常通知；

1，前置通知；

T.java:

 1 package com.wishwzp.test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.wishwzp.service.StudentService;
 7 
 8 
 9 public class T {
10 
11     public static void main(String[] args) {
12         ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
13         StudentService studentService=(StudentService)ac.getBean("studentService");
14         studentService.addStudent("张三");
15         
16     }
17 }

beans.xml:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:aop="http://www.springframework.org/schema/aop"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans
 6         http://www.springframework.org/schema/beans/spring-beans.xsd
 7         http://www.springframework.org/schema/aop
 8         http://www.springframework.org/schema/aop/spring-aop.xsd">
 9     
10     <!-- 注入bean，StudentServiceAspect -->
11     <bean id="studentServiceAspect" class="com.wishwzp.advice.StudentServiceAspect"></bean>
12     
13     <!-- 注入bean，StudentServiceImpl -->
14     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
15     
16     <!-- 配置AOP -->
17     <aop:config>
18         <aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
19             <aop:pointcut expression="execution(* com.wishwzp.service.*.*(..))" id="businessService"/>
20             <aop:before method="doBefore" pointcut-ref="businessService"/>
21         </aop:aspect> 
22     </aop:config>
23 </beans>

StudentServiceAspect.java:

 1 package com.wishwzp.advice;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.ProceedingJoinPoint;
 5 
 6 public class StudentServiceAspect {
 7 
 8     public void doBefore(JoinPoint jp){
 9         System.out.println("类名:"+jp.getTarget().getClass().getName());
10         System.out.println("方法名："+jp.getSignature().getName());
11         System.out.println("开始添加学生："+jp.getArgs()[0]);
12     }
13     
14 }

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public void addStudent(String name) {
 9         // System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         // System.out.println("完成学生"+name+"的添加");
12     }
13 
14 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public void addStudent(String name);
6 }

运行结果显示：

类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
开始添加学生：张三
添加学生张三

2，后置通知；

T.java:

 1 package com.wishwzp.test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.wishwzp.service.StudentService;
 7 
 8 
 9 public class T {
10 
11     public static void main(String[] args) {
12         ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
13         StudentService studentService=(StudentService)ac.getBean("studentService");
14         studentService.addStudent("张三");
15         
16     }
17 }

beans.xml:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:aop="http://www.springframework.org/schema/aop"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans
 6         http://www.springframework.org/schema/beans/spring-beans.xsd
 7         http://www.springframework.org/schema/aop
 8         http://www.springframework.org/schema/aop/spring-aop.xsd">
 9     
10     <!-- 注入bean，StudentServiceAspect -->
11     <bean id="studentServiceAspect" class="com.wishwzp.advice.StudentServiceAspect"></bean>
12     
13     <!-- 注入bean，StudentServiceImpl -->
14     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
15     
16     <!-- 配置AOP -->
17     <aop:config>
18         <aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
19             <!-- 配置执行切点路径和id -->
20             <aop:pointcut expression="execution(* com.wishwzp.service.*.*(..))" id="businessService"/>
21             <!-- 前置通知 -->
22             <aop:before method="doBefore" pointcut-ref="businessService"/>
23             <!-- 后置通知 -->
24             <aop:after method="doAfter" pointcut-ref="businessService"/>
25         </aop:aspect> 
26     </aop:config>
27 </beans>

StudentServiceAspect.java:

 1 package com.wishwzp.advice;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.ProceedingJoinPoint;
 5 
 6 public class StudentServiceAspect {
 7 
 8     //前置通知
 9     public void doBefore(JoinPoint jp){
10         System.out.println("类名:"+jp.getTarget().getClass().getName());
11         System.out.println("方法名："+jp.getSignature().getName());
12         System.out.println("开始添加学生："+jp.getArgs()[0]);
13     }
14     
15     //后置通知
16     public void doAfter(JoinPoint jp){
17         System.out.println("类名:"+jp.getTarget().getClass().getName());
18         System.out.println("方法名："+jp.getSignature().getName());
19         System.out.println("学生添加完成："+jp.getArgs()[0]);
20     }
21 }

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public void addStudent(String name) {
 9         // System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         // System.out.println("完成学生"+name+"的添加");
12     }
13 
14 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public void addStudent(String name);
6 }

运行结果显示：

类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
开始添加学生：张三
添加学生张三
类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
学生添加完成：张三

3，环绕通知；

T.java:

 1 package com.wishwzp.test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.wishwzp.service.StudentService;
 7 
 8 
 9 public class T {
10 
11     public static void main(String[] args) {
12         ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
13         StudentService studentService=(StudentService)ac.getBean("studentService");
14         studentService.addStudent("张三");
15         
16     }
17 }

beans.xml:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:aop="http://www.springframework.org/schema/aop"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans
 6         http://www.springframework.org/schema/beans/spring-beans.xsd
 7         http://www.springframework.org/schema/aop
 8         http://www.springframework.org/schema/aop/spring-aop.xsd">
 9     
10     <!-- 注入bean，StudentServiceAspect -->
11     <bean id="studentServiceAspect" class="com.wishwzp.advice.StudentServiceAspect"></bean>
12     
13     <!-- 注入bean，StudentServiceImpl -->
14     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
15     
16     <!-- 配置AOP -->
17     <aop:config>
18         <aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
19             <!-- 配置执行切点路径和id -->
20             <aop:pointcut expression="execution(* com.wishwzp.service.*.*(..))" id="businessService"/>
21             <!-- 前置通知 -->
22             <aop:before method="doBefore" pointcut-ref="businessService"/>
23             <!-- 后置通知 -->
24             <aop:after method="doAfter" pointcut-ref="businessService"/>
25             <!-- 环绕通知 -->
26             <aop:around method="doAround" pointcut-ref="businessService"/>
27         </aop:aspect> 
28     </aop:config>
29 </beans>

StudentServiceAspect.java:

 1 package com.wishwzp.advice;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.ProceedingJoinPoint;
 5 
 6 public class StudentServiceAspect {
 7 
 8     //前置通知
 9     public void doBefore(JoinPoint jp){
10         System.out.println("类名:"+jp.getTarget().getClass().getName());
11         System.out.println("方法名："+jp.getSignature().getName());
12         System.out.println("开始添加学生："+jp.getArgs()[0]);
13     }
14     
15     //后置通知
16     public void doAfter(JoinPoint jp){
17         System.out.println("类名:"+jp.getTarget().getClass().getName());
18         System.out.println("方法名："+jp.getSignature().getName());
19         System.out.println("学生添加完成："+jp.getArgs()[0]);
20     }
21     
22     //环绕通知,这里添加了返回值
23     public Object doAround(ProceedingJoinPoint pjp) throws Throwable{
24         System.out.println("添加学生前");
25         Object retVal=pjp.proceed();
26         System.out.println(retVal);
27         System.out.println("添加学生后");
28         return retVal;
29     }
30 }

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public String addStudent(String name) {
 9         // System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         // System.out.println("完成学生"+name+"的添加");
12         return name;
13     }
14 
15 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public String addStudent(String name);
6 }

运行结果显示：

类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
开始添加学生：张三
添加学生前
添加学生张三
张三
添加学生后
类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
学生添加完成：张三

4，返回通知；

T.java:

 1 package com.wishwzp.test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.wishwzp.service.StudentService;
 7 
 8 
 9 public class T {
10 
11     public static void main(String[] args) {
12         ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
13         StudentService studentService=(StudentService)ac.getBean("studentService");
14         studentService.addStudent("张三");
15         
16     }
17 }

beans.xml:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:aop="http://www.springframework.org/schema/aop"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans
 6         http://www.springframework.org/schema/beans/spring-beans.xsd
 7         http://www.springframework.org/schema/aop
 8         http://www.springframework.org/schema/aop/spring-aop.xsd">
 9     
10     <!-- 注入bean，StudentServiceAspect -->
11     <bean id="studentServiceAspect" class="com.wishwzp.advice.StudentServiceAspect"></bean>
12     
13     <!-- 注入bean，StudentServiceImpl -->
14     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
15     
16     <!-- 配置AOP -->
17     <aop:config>
18         <aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
19             <!-- 配置执行切点路径和id -->
20             <aop:pointcut expression="execution(* com.wishwzp.service.*.*(..))" id="businessService"/>
21             <!-- 前置通知 -->
22             <aop:before method="doBefore" pointcut-ref="businessService"/>
23             <!-- 后置通知 -->
24             <aop:after method="doAfter" pointcut-ref="businessService"/>
25             <!-- 环绕通知 -->
26             <aop:around method="doAround" pointcut-ref="businessService"/>
27             <!-- 返回通知 -->
28             <aop:after-returning method="doAfterReturning" pointcut-ref="businessService"/>
29         </aop:aspect> 
30     </aop:config>
31 </beans>

StudentServiceAspect.java:

 1 package com.wishwzp.advice;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.ProceedingJoinPoint;
 5 
 6 public class StudentServiceAspect {
 7 
 8     //前置通知
 9     public void doBefore(JoinPoint jp){
10         System.out.println("类名:"+jp.getTarget().getClass().getName());
11         System.out.println("方法名："+jp.getSignature().getName());
12         System.out.println("开始添加学生："+jp.getArgs()[0]);
13     }
14     
15     //后置通知
16     public void doAfter(JoinPoint jp){
17         System.out.println("类名:"+jp.getTarget().getClass().getName());
18         System.out.println("方法名："+jp.getSignature().getName());
19         System.out.println("学生添加完成："+jp.getArgs()[0]);
20     }
21     
22     //环绕通知,这里添加了返回值
23     public Object doAround(ProceedingJoinPoint pjp) throws Throwable{
24         System.out.println("添加学生前");
25         Object retVal=pjp.proceed();
26         System.out.println(retVal);
27         System.out.println("添加学生后");
28         return retVal;
29     }
30     
31     //返回通知
32     public void doAfterReturning(JoinPoint jp){
33         System.out.println("返回通知");
34     }
35 }

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public String addStudent(String name) {
 9         // System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         // System.out.println("完成学生"+name+"的添加");
12         return name;
13     }
14 
15 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public String addStudent(String name);
6 }

运行结果显示：

类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
开始添加学生：张三
添加学生前
添加学生张三
返回通知
张三
添加学生后
类名:com.wishwzp.service.impl.StudentServiceImpl
方法名：addStudent
学生添加完成：张三

5，异常通知；

T.java:

 1 package com.wishwzp.test;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 import com.wishwzp.service.StudentService;
 7 
 8 
 9 public class T {
10 
11     public static void main(String[] args) {
12         ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
13         StudentService studentService=(StudentService)ac.getBean("studentService");
14         studentService.addStudent("张三");
15         
16     }
17 }

beans.xml:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:aop="http://www.springframework.org/schema/aop"
 5     xsi:schemaLocation="http://www.springframework.org/schema/beans
 6         http://www.springframework.org/schema/beans/spring-beans.xsd
 7         http://www.springframework.org/schema/aop
 8         http://www.springframework.org/schema/aop/spring-aop.xsd">
 9     
10     <!-- 注入bean，StudentServiceAspect -->
11     <bean id="studentServiceAspect" class="com.wishwzp.advice.StudentServiceAspect"></bean>
12     
13     <!-- 注入bean，StudentServiceImpl -->
14     <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl"></bean>
15     
16     <!-- 配置AOP -->
17     <aop:config>
18         <aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
19             <!-- 配置执行切点路径和id -->
20             <aop:pointcut expression="execution(* com.wishwzp.service.*.*(..))" id="businessService"/>
21             <!-- 前置通知 -->
22             <aop:before method="doBefore" pointcut-ref="businessService"/>
23             <!-- 后置通知 -->
24             <aop:after method="doAfter" pointcut-ref="businessService"/>
25             <!-- 环绕通知 -->
26             <aop:around method="doAround" pointcut-ref="businessService"/>
27             <!-- 返回通知 -->
28             <aop:after-returning method="doAfterReturning" pointcut-ref="businessService"/>
29             <!-- 异常通知 -->
30             <aop:after-throwing method="doAfterThrowing" pointcut-ref="businessService" throwing="ex"/>
31         </aop:aspect> 
32     </aop:config>
33 </beans>

StudentServiceAspect.java:

 1 package com.wishwzp.advice;
 2 
 3 import org.aspectj.lang.JoinPoint;
 4 import org.aspectj.lang.ProceedingJoinPoint;
 5 
 6 public class StudentServiceAspect {
 7 
 8     //前置通知
 9     public void doBefore(JoinPoint jp){
10         System.out.println("类名:"+jp.getTarget().getClass().getName());
11         System.out.println("方法名："+jp.getSignature().getName());
12         System.out.println("开始添加学生："+jp.getArgs()[0]);
13     }
14     
15     //后置通知
16     public void doAfter(JoinPoint jp){
17         System.out.println("类名:"+jp.getTarget().getClass().getName());
18         System.out.println("方法名："+jp.getSignature().getName());
19         System.out.println("学生添加完成："+jp.getArgs()[0]);
20     }
21     
22     //环绕通知,这里添加了返回值
23     public Object doAround(ProceedingJoinPoint pjp) throws Throwable{
24         System.out.println("添加学生前");
25         Object retVal=pjp.proceed();
26         System.out.println(retVal);
27         System.out.println("添加学生后");
28         return retVal;
29     }
30     
31     //返回通知
32     public void doAfterReturning(JoinPoint jp){
33         System.out.println("返回通知");
34     }
35     
36     //异常通知
37     public void doAfterThrowing(JoinPoint jp,Throwable ex){
38         System.out.println("异常通知");
39         System.out.println("异常信息："+ex.getMessage());
40     }
41 }

StudentServiceImpl.java:

 1 package com.wishwzp.service.impl;
 2 
 3 import com.wishwzp.service.StudentService;
 4 
 5 public class StudentServiceImpl implements StudentService{
 6 
 7     @Override
 8     public String addStudent(String name) {
 9         // System.out.println("开始添加学生"+name);
10         System.out.println("添加学生"+name);
11         System.out.println(1/0);
12         // System.out.println("完成学生"+name+"的添加");
13         return name;
14     }
15 
16 }

StudentService.java:

1 package com.wishwzp.service;
2 
3 public interface StudentService {
4 
5     public String addStudent(String name);
6 }

运行结果显示：

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