Spring AOP基于注解的应用

让我们写一个Spring AOP基于注解的应用例子,它将使用基于注解的配置实现通知。打开并使用Eclipse IDE,并按照以下步骤创建一个Spring应用程序:

  1. 更新在Spring AOP应用实例中创建过的Student项目。
  2. 更新bean配置并运行应用程序,如下所述。

整个项目的目录结构如下所示 -

下面是Logging.java文件的内容。 这实际上是一个Aspect模块的样本,它定义了在各个点被调用的方法。

package com.zyiz;

import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;

@Aspect
public class Logging {

   /** Following is the definition for a pointcut to select
    *  all the methods available. So advice will be called
    *  for all the methods.
    */
   @Pointcut("execution(* com.zyiz.*.*(..))")
   private void selectAll(){}

   /** 
    * This is the method which I would like to execute
    * before a selected method execution.
    */
   @Before("selectAll()")
   public void beforeAdvice(){
      System.out.println("[beforeAdvice] Going to setup student profile.");
   }  
}

以下是Student.java文件的内容:

package com.zyiz;

public class Student {
   private Integer age;
   private String name;

   public void setAge(Integer age) {
      this.age = age;
   }
   public Integer getAge() {
      System.out.println("Age : " + age );
      return age;
   }

   public void setName(String name) {
      this.name = name;
   }
   public String getName() {
      System.out.println("Name : " + name );
      return name;
   }
   public void printThrowException(){
      System.out.println("Exception raised");
      throw new IllegalArgumentException();
   }
}

以下是MainApp.java文件的内容:

package com.zyiz;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainApp {
   public static void main(String[] args) {
      ApplicationContext context = 
             new ClassPathXmlApplicationContext("Beans.xml");

      Student student = (Student) context.getBean("student");

      student.getName();
      student.getAge();   
   }
}

以下是配置文件Beans.xml文件的内容:

<?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-3.0.xsd 
    http://www.springframework.org/schema/aop 
    http://www.springframework.org/schema/aop/spring-aop-3.0.xsd ">

    <aop:aspectj-autoproxy/>

   <!-- Definition for student bean -->
   <bean id="student" class="com.zyiz.Student">
      <property name="name"  value="minsu" />
      <property name="age"  value="25"/>      
   </bean>

   <!-- Definition for logging aspect -->
   <bean id="logging" class="com.zyiz.Logging"/> 

</beans>

运行项目

完成创建源代码和配置文件后,运行应用程序。右键单击应用程序中的MainApp.java,并使用运行方式作为Java应用程序命令。 如果您的应用程序一切正常,这将打印以下消息:

[beforeAdvice] Going to setup student profile.
Name : minsu
[beforeAdvice] Going to setup student profile.
Age : 25

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