标签：功能 des org java text out imp ora pre
1、概述
1.1、Spring提供了大量的注解，
尤其是相同的注解用到各个类中，会相当的啰嗦；
1.2、元注解：
可以注解到别的注解上的注解；
组合注解：
被注解注解的注解称为 组合注解；
组合注解 具备 元注解 的功能，Spring的很多注解都可以作为元注解；
1.3、案例
package com.an.config;
import com.an.annotation.MyAnnotation;
/**
* @description:
* @author: anpeiyong
* @date: Created in 2019/11/21 8:57
* @since:
*/
@MyAnnotation(value = "com.an")
public class AnnotationConfig {
}
package com.an.annotation;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @description:
* @author: anpeiyong
* @date: Created in 2019/11/21 8:47
* @since:
*/
@Target(value = ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Configuration
@ComponentScan
public @interface MyAnnotation {
String[] value() default {};
}
package com.an.annotation;
import org.springframework.stereotype.Service;
/**
* @description:
* @author: anpeiyong
* @date: Created in 2019/11/21 8:54
* @since:
*/
@Service
public class AnnotationService {
public void output(){
System.out.println("组合注解成功。。。");
}
}
package com.an.main;
import com.an.annotation.AnnotationService;
import com.an.config.AnnotationConfig;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
/**
* @description:
* @author: anpeiyong
* @date: Created in 2019/11/21 8:57
* @since:
*/
public class AnnotationMainTest {
public static void main(String[] args) {
AnnotationConfigApplicationContext annotationConfigApplicationContext=new AnnotationConfigApplicationContext(AnnotationConfig.class);
AnnotationService annotationService=annotationConfigApplicationContext.getBean(AnnotationService.class);
annotationService.output();
annotationConfigApplicationContext.close();
}
}
结果：
组合注解成功。。。
标签：功能 des org java text out imp ora pre
原文地址：https://www.cnblogs.com/anpeiyong/p/11903509.html
