注解example

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Retention(RetentionPolicy.RUNTIME)
public @interface myAnnotation {
	String name() default "abc";
}
import java.lang.annotation.Annotation;

@myAnnotation
public class A {
	@myAnnotation
	public void a(){
		
	}
	public static void main(String[] args) throws Exception {
		System.out.println("测试annotation的默认值");
		A b = new A();
		myAnnotation annotations = b.getClass().getMethod("a",null).getAnnotation(myAnnotation.class);
		System.out.println(annotations.name().toString());
	}
}