java学习笔记----枚举测试题

定义义一个交通灯枚举类，包含红灯、绿灯、黄灯，需要有获得下一个灯的方法，并实现红灯出现5秒之后变成绿灯，绿灯3秒之后变成黄灯，黄灯2秒之后变成红灯,如此循环

public class Test5 {

     /**
      * @throws InterruptedException
      */
     public static void main(String[] args) throws InterruptedException {
          Deng[] deng = Deng. values();
           for( int i = 0;i < 3;i++){
              Deng d = deng[i];
               if(d == Deng. red){
                   System. out.println(d);
                   Thread. sleep(5000);
                   System. out.println(d.next());
              } else if(d == Deng. green){
                   Thread. sleep(3000);
                   System. out.println(d.next());
              } else if(d == Deng. yellow){
                   Thread. sleep(2000);
//                 System.out.println(d.next());
                   i = -1;
              }
          }
     }
}
enum Deng{
     red("红灯"){
           public Deng next(){
               return green;
          }
     },green("绿灯"){
           public Deng next(){
               return yellow;
          }
     },yellow("黄灯"){
           public Deng next(){
               return red;
          }
     };
     public abstract Deng next();
     private String name;
     private Deng(String name){
           this. name = name;
     }
     @Override
     public String toString() {
           return name;
     }
}