Annotation(어노테이션)

Annotation : class, 메소드, 생성자, 변수 위에 선언

- annotation명 [("element")]    (element="value", element="value....)

1. 검증 : 구문을 compile 시점에 검증

2. 설정 : XML 설정

Aspect 어노테이션을 이용한 AOP(Aspect Oriented Programming)

- Aspect 어노테이션을 이용하여 Aspect 클래스에 직접 Advice 및 Pointcut 등을 설정

- 설정 파일에 <aop:aspectj-autoproxy/>를 추가 해야함

- Aspect Class를 <bean>으로 등록

- Annotation(어노테이션)

* @Aspect : Aspect 클래스 선언

* @Before("pointcut")

* @AfterReturning(pointcut="", returning="")

* @AfterThrowing(pointcut="", throwing="")

* @After("pointcut")

* @Around("pointcut")

- Around를 제외한 나머지 메소드들은 첫 argument로 JoinPoint를 가질 수 있다.

- Around 메소드는 argument로 ProceedingJoinPoint를 가질 수 있다.

CoreClass.java

package aop.core;

public class CoreClass {

public void businessMethod(int i) {

if(i<0) {

throw new RuntimeException("i가 0보다 작다");

}

System.out.println("Business메소드가 실행 되었습니다.");

}

}

AdviceClass.java

package aop.common;

import org.aspectj.lang.ProceedingJoinPoint;

import org.aspectj.lang.annotation.After;

import org.aspectj.lang.annotation.AfterReturning;

import org.aspectj.lang.annotation.AfterThrowing;

import org.aspectj.lang.annotation.Around;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Before;

@Aspect //aspect 클래스 선언

public class AdviceClass {

@Before("within(aop.core.CoreClass)") //pointcut 입력

public void beforeLogger() {

System.out.println("Advice Class.beforeLogger()------------");

}

@AfterThrowing(pointcut="within(aop.core.CoreClass)", throwing="ex")

public void afterThrowLogger(Throwable ex) {

System.out.println("AdviceClass.afterThrowLogger()------------");

System.out.println(ex.getMessage());

}

@AfterReturning(pointcut="within(aop.core.CoreClass)", returning="ret")

public void afterReturnLogger(Object ret) {

System.out.println("AdviceClass.afterReturnLogger()------------");

System.out.println(ret);

}

@After("within(aop.core.CoreClass)")

public void afterLogger() {

System.out.println("AdviceClass.afterLogger()----------");

}

@Around("within(aop.core.CoreClass)")

public Object aroundLogger(ProceedingJoinPoint jp) throws Throwable {

System.out.println("AdviceClass.aroundLogger()----------");

return jp.proceed();

}

}

aop.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/>

<!-- 타겟 -->

<bean name="core" class="aop.core.CoreClass"/>

<!-- Advice -->

<bean name="advice" class="aop.common.AdviceClass"/>

</beans>

TestMain.java

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import aop.core.CoreClass;

public class TestMain {

public static void main(String[] args) {

ApplicationContext ctx = new ClassPathXmlApplicationContext("aop/config/aop.xml");

CoreClass cls = (CoreClass) ctx.getBean("core");

cls.businessMethod(-20);

}

}

실행결과