Spring-AOP @AspectJ進階之繫結類註解物件
阿新 • • 發佈:2019-01-05
概述
@within()和@target()函式可以將目標類的註解物件繫結到增強方法中。
我們通過@within()演示註解繫結的操作
例項
註解(使用的是自定義註解,也可以使用框架提供的註解)
package com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation .Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
//宣告註解的保留期限
@Retention(RetentionPolicy.RUNTIME)
// 宣告可以使用該註解的目標型別
@Target(ElementType.TYPE)
// 可以被javadoc此類的工具文件化
@Documented
public @interface Monitor { // 定義註解
// 宣告註解成員
boolean value() default false;
}
業務類
package com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj;
import org.springframework.stereotype.Component;
/**
*
*
* @ClassName: Bussiness
*
* @Description: bean使用@Component註解,
*
* 同時標註了@@Monitor註解,所有Bussiness Bean匹配切點, 其@Monitor註解物件將繫結到增強方法中
*
* @author: Mr.Yang
*
* @date : 2017年9月12日 下午4:32:23
*/
@Component
@Monitor
public class Bussiness {
public void dealBussinessOne() {
System.out.println("dealBussinessOne executed");
}
public void dealBussinessTwo() {
System.out.println("dealBussinessTwo executed");
}
}
切面
package com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
/**
*
*
* @ClassName: BindTypeAnnoObjectAspect
*
* @Description: @Aspect標註的切面
*
* (1)通過(2)處查找出m對應Monitor型別的註解, 因而真實的切點表示式為@within
* (Monitor),當增強方法織入目標 連線點時,增強方法通過m入參可以引用到連線點處的註解物件。
*
* @author: Mr.Yang
*
* @date: 2017年9月12日 下午4:27:55
*/
@Aspect
public class BindTypeAnnoObjectAspect {
// (1)
@Before("@within(m)")
public void bindTypeAnno(Monitor m) { // (2)
System.out.println("----bindTypeAnnoObject()----");
System.out.println(m.getClass().getName());
System.out.println("----bindTypeAnnoObject()----");
}
}
(1)通過(2)處查找出m對應Monitor型別的註解, 因而真實的切點表示式為@within(Monitor),當增強方法織入目標 連線點時,增強方法通過m入參可以引用到連線點處的註解物件。
配置檔案
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
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
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- (1)宣告Context名稱空間以及Schema檔案 (2)掃描類包以及應用註解定義的bean -->
<context:component-scan base-package="com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj"/>
<!-- 基於@AspectJ切面的驅動器 -->
<aop:aspectj-autoproxy proxy-target-class="true"/>
<!-- 使用了@AspectJ註解的切面類 -->
<bean class="com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj.BindTypeAnnoObjectAspect"/>
</beans>
測試類
package com.xgj.aop.spring.advisor.aspectJAdvance.bindTypeAnnoObj;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class BindTypeAnnoObjectAspectTest {
@Test
public void test() {
ApplicationContext ctx = new ClassPathXmlApplicationContext(
"classpath:com/xgj/aop/spring/advisor/aspectJAdvance/bindTypeAnnoObj/conf-bindTypeAnnoObj.xml");
Bussiness bussiness = ctx.getBean("bussiness", Bussiness.class);
bussiness.dealBussinessOne();
bussiness.dealBussinessTwo();
}
}
輸出結果
2017-09-12 16:58:15,464 INFO [main] (AbstractApplicationContext.java:583) - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@292898f5: startup date [Tue Sep 12 16:58:15 BOT 2017]; root of context hierarchy
2017-09-12 16:58:15,684 INFO [main] (XmlBeanDefinitionReader.java:317) - Loading XML bean definitions from class path resource [com/xgj/aop/spring/advisor/aspectJAdvance/bindTypeAnnoObj/conf-bindTypeAnnoObj.xml]
----bindTypeAnnoObject()----
com.sun.proxy.$Proxy6
----bindTypeAnnoObject()----
dealBussinessOne executed
----bindTypeAnnoObject()----
com.sun.proxy.$Proxy6
----bindTypeAnnoObject()----
dealBussinessTwo executed
從輸出資訊中,com.sun.proxy.$Proxy6,即使用CGLib代理NaiveWaiter時,其類的註解Monitorable物件也被代理了.