012. Spring Aspect Oriented Programming(AOP)

1、创建Java项目：File -> New -> Java Project

2、引入必要jar包，项目结构如下



3、创建StudentService接口StudentService.java

package com.spring.service;

public interface StudentService {

public void saveStudent(String student);

}

4、创建StudentServiceImp实现类StudentServiceImp.java

package com.spring.service.imp;

import com.spring.service.StudentService;

public class StudentServiceImp implements StudentService {

@Override
public void saveStudent(String student) {

System.out.println("invoke saveStudent(String student) Save student: " + student);
// System.out.println(1/0); // 测试异常通知
}

}

5、创建StudentServiceAspect切面类StudentServiceAspect.java

package com.spring.advice;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;

public class StudentServiceAspect {

public void doBefore(JoinPoint jp ) {
System.out.println("前置通知开始");
System.out.println("Class name: " + jp.getTarget().getClass().getName());
System.out.println("Function name: " + jp.getSignature().getName());
System.out.println("Save student begin: " + jp.getArgs()[0]);
System.out.println("前置通知结束");
}

public void doAfter(JoinPoint jp) {
System.out.println("后置通知开始");
System.out.println("Class name: " + jp.getTarget().getClass().getName());
System.out.println("Function name: " + jp.getSignature().getName());
System.out.println("Save student end: " + jp.getArgs()[0]);
System.out.println("后置通知结束");
}

public Object doAround(ProceedingJoinPoint pjp) {

System.out.println("环绕通知开始");

Object retVal = null; // 函数返回值

try {
retVal = pjp.proceed(); // 调用函数
} catch (Throwable e) {
e.printStackTrace();
}
System.out.println("函数执行结果: " + retVal);

System.out.println("环绕通知结束");
return retVal;
}

public void doAfterReturning(JoinPoint jp) {
System.out.println("返回通知");
}

public void doAfterThrowing(JoinPoint jp, Throwable e){
System.out.println("异常通知: " + e.getMessage());
}

}

6、创建spring配置文件applicationContext.xml

<?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: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/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> 
<bean id="studentServiceAspect" class="com.spring.advice.StudentServiceAspect"></bean>

<bean id="studentService" class="com.spring.service.imp.StudentServiceImp"></bean>

<aop:config>
<aop:aspect id="studentServiceAspect" ref="studentServiceAspect">
<aop:pointcut expression="execution(* com.spring.service.*.*(..))" id="advice" />
<aop:before method="doBefore" pointcut-ref="advice"/>
<aop:after method="doAfter" pointcut-ref="advice"/>
<aop:around method="doAround" pointcut-ref="advice"/>
<aop:after-returning method="doAfterReturning" pointcut-ref="advice"/>
<aop:after-throwing method="doAfterThrowing" pointcut-ref="advice" throwing="e"/>
</aop:aspect>
</aop:config>

</beans>

7、创建Spring测试类SpringUnit.java

package com.spring.junit;

import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.spring.service.StudentService;

public class SpringUnit {

@Test
public void test() {

ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");

StudentService studentService = (StudentService) ctx.getBean("studentService");
studentService.saveStudent("吴腾辉");

ctx.close();
}

}

8、测试结果

... 省略Spring日志信息 ...

前置通知开始
Class name: com.spring.service.imp.StudentServiceImp
Function name: saveStudent
Save student begin: 吴腾辉
前置通知结束
环绕通知开始
invoke saveStudent(String student) Save student: 吴腾辉
返回通知
函数执行结果: null
环绕通知结束
后置通知开始
Class name: com.spring.service.imp.StudentServiceImp
Function name: saveStudent
Save student end: 吴腾辉
后置通知结束

... 省略Spring日志信息 ...