Springaop 简明教程

Spring AOP - Annotation Based Application

让我们编写一个基于注释的配置将实现通知的示例。为此,让我们使用现有的 Eclipse IDE,并按照以下步骤创建一个 Spring 应用程序。

Step

Description

1

更新在章节 Spring AOP - Application 创建的学生项目。

2

更新 bean 配置并按如下说明运行应用程序。

以下是 Logging.java 文件的内容。这实际上是方面模块的一个示例,它定义了在各个点调用的方法。

package com.tutorialspoint;

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.tutorialspoint.*.*(..))")
   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("Going to setup student profile.");
   }
}

以下是 Student.java 文件的内容。

package com.tutorialspoint;

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.tutorialspoint;

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

<?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.tutorialspoint.Student">
      <property name = "name"  value = "Zara" />
      <property name = "age"  value = "11"/>
   </bean>

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

Run Project

创建源和配置文件后,运行您的应用程序。在应用程序中右键单击 MainApp.java 并使用 run as Java Application 命令。如果您的应用程序一切正常,它将打印以下消息。

Going to setup student profile.
Name : Zara
Going to setup student profile.
Age : 11