aop 例子学习,转自javaeye
首先建一个普通Java项目:com.longthsoft.learn.spring
把 spring.jar, commons-logging.jar, cglib-nodep-...jar, aspectjweaver.jar, aspectjrt.jar 放到 Build Path 下.
以止 lib 除了 spring 外, 其他的都可以在 spring 下载包的 lib 中找到
下面编码开始:
让我们先写两个简单的类:
代码
1 package om.longthsoft.learn.spring.models;
2
3 public class A {
4 public void sayHello() {
5 System.out.println("Hello, I'm a");
6 }
7 }
8
1 package com.longthsoft.learn.spring.models;
2 public class B {
3 public void sayHi() {
4 System.out.println("Hi, I'm b");
5 }
6 }
7
没什么实际的东西, 只是小A和小B在打招呼
接下来把他们交给Spring吧(有点残忍)。
代码
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="
6 http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
7 http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
8
9 <bean id="a" class="com.longthsoft.learn.spring.models.A" />
10 <bean id="b" class="com.longthsoft.learn.spring.models.B" />
11 </beans>
12
接下来写个Boot
代码
1 package com.longthsoft.learn.spring;
2
3 import org.springframework.context.ApplicationContext;
4 import org.springframework.context.support.ClassPathXmlApplicationContext;
5
6 import com.longthsoft.learn.spring.models.A;
7 import com.longthsoft.learn.spring.models.B;
8
9 public final class Boot {
10
11 public static void main(String[] args) {
12 ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
13 A a = (A) ctx.getBean("a");
14 a.sayHello();
15
16 B b = (B) ctx.getBean("b");
17 b.sayHi();
18 }
19
20 }
21
嘿, 这里的运行结果不帖了, 大家脑子里闪过即可。
圣诞到了, 小A小B 介绍完自己之后,也应该说句 "Merry Christmas"
Spring 说, 既然你们交给我, 这等 routine 就不用再麻烦了, 直接一并处理掉。
于是:
代码
1 package com.longthsoft.learn.spring;
2
3 import org.aspectj.lang.annotation.AfterReturning;
4 import org.aspectj.lang.annotation.Aspect;
5 import org.aspectj.lang.annotation.Pointcut;
6
7 @Aspect
8 public class SimpleAspect {
9
10 @Pointcut("execution(* com.longthsoft.learn.spring.models.*.say*())")
11 public void simplePointcut() { }
12
13 @AfterReturning(pointcut="simplePointcut()")
14 public void simpleAdvice() {
15 System.out.println("Merry Christmas");
16 }
17 }
18
然后修改一下配置文件
代码
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="
6 http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
7 http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
8
9 <aop:aspectj-autoproxy />
10
11 <bean id="a" class="com.longthsoft.learn.spring.models.A" />
12 <bean id="b" class="com.longthsoft.learn.spring.models.B" />
13
14 <bean id="simpleAspect" class="com.longthsoft.learn.spring.SimpleAspect" />
15 </beans>
16
OK, 运行一下:
Hello, I'm a
Merry Christmas
Hi, I'm b
Merry Christmas