Java中的Enum的继承

public    interface Icolor{

       int apply(int x,int y);
    }

 public enum color implements Icolor{

     plus("+"){

        public int apply(int x,int y){ return x+y;}
     },
     min("-"){

        public int apply(int x,int y){ return x-y;}
     }

     ;

          private final String num;
          color(String num){
              this.num=num;
          }

     }

//调用 color.plus.apply(100, 1)