Spring @Required 어노테이션(Annotation)

전제 조건
 applicationContext.xml 에

<bean class="org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor" />


 

applicationContext.xml

Camera.java

package madvirus.spring.chap04.homecontrol;

import org.springframework.beans.factory.annotation.Required;

public class Camera {

	private int number;

	public Camera(){
	}
	
	@Required
	public void setNumber(int number) {
		this.number = number;
	}
	@Override
	public String toString() {
		return "Camera [number=" + number + "]";
	}	
}

Main.java

package madvirus.spring.chap04.homecontrol;

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

public class Main {
	public static void main(String[] args) {
		String[] configLocations = new String[] { "applicationContext.xml" };
		ApplicationContext context = new ClassPathXmlApplicationContext(
				configLocations);

		Camera camera = context.getBean("camera1", Camera.class);
		System.out.println(camera);
	}
}

Camera.java

setNumber에 반드시 데이터를 넘기라는 표현
Spring에서만 사용할 수 있는 방법 

짧은 표현 방법

<bean class="org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor" />를

<context:annotation-config /> 로 대처해도 실행화면은 같다

실행 화면 (Main.java)

Camera [number=1]

 

※※※※※※※※※※※

-RequiredAnnotationBeanPostProcessor  :@Required 사용시

-AutowiredAnnotationBeanPostProcessor : @Autowired 사용시

-CommonAnnotationBeanPostProcessor : @Resource,@PostConstruct , @PreDestroy 사용시

-ConfigurationClassPostProcessor : @Configuration 사용시

<context:annotation-config />

로 모두 대처 가능함