一种别样的鉴权方式 注解 + 接口 + 枚举 妙用

/**
* Authentication interface
* @author keane
*
*/
public interface IIdentify {
String INFO = "no permiss";
public boolean verify();
}

/**
* Authentication impl
*
* @author keane
*
*/
public enum IdentifyType implements IIdentify{
//level
READER(true),AUTHOR(true),ADMIN;

private boolean allow;

private IdentifyType() {
this.allow = false;
}

private IdentifyType(boolean allow) {
this.allow = allow;
}

//impl
@Override
public boolean verify() {
return allow;
}
}

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

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface Access {
//what's access
IdentifyType level() default IdentifyType.READER;

}

/**
* access entity
* @author keane
*
*/
@Access(level=IdentifyType.AUTHOR)
public class FaceBook {

}

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
if(FaceBook.class.isAnnotationPresent(Access.class)){
Access access = FaceBook.class.getAnnotation(Access.class);
if(access == null || !access.level().verify()){
System.out.println("no," + access.level().INFO);
}else{
System.out.println("yes,welcome!");
}
}else{
System.out.println("nothing!");
}

}

}