枚举

package com.loaderman.枚举;

public class Demo1_Enum {

    /**
     * @param args
     */
    public static void main(String[] args) {
        //demo1();
        //demo2();
        //demo3();
        Week3 mon = Week3.TUE;
        switch (mon) {
            case MON:
                System.out.println("星期一");
                break;
            case TUE:
                System.out.println("星期二");
                break;
        }
    }

    public static void demo3() {
        Week3 mon = Week3.MON;
        mon.show();
    }

    public static void demo2() {
        Week2 mon = Week2.MON;
        System.out.println(mon.getName());
    }

    public static void demo1() {
        Week mon = Week.MON;
        System.out.println(mon);
    }

}

 

package com.loaderman.枚举;

public class Demo2_Enum {

    /**
     * int ordinal()
     * int compareTo(E o)
     * String name()
     * String toString()
     * <T> T valueOf(Class<T> type,String name)
     * values() 
     * 此方法虽然在JDK文档中查找不到，但每个枚举类都具有该方法，它遍历枚举类的所有枚举值非常方便
     */
    public static void main(String[] args) {
        //demo1();
        //    Week2 mon = Week2.valueOf(Week2.class, "MON");    //通过字节码对象获取枚举项
        //    System.out.println(mon);

        Week2[] arr = Week2.values();
        for (Week2 week2 : arr) {
            System.out.println(week2);
        }
    }

    public static void demo1() {
        Week2 mon = Week2.MON;
        Week2 tue = Week2.TUE;
        Week2 wed = Week2.WED;
      
      /*System.out.println(mon.ordinal());            //枚举项都是有编号的
      System.out.println(tue.ordinal());
      System.out.println(wed.ordinal());
      
      System.out.println(mon.compareTo(tue));          //比较的是编号
      System.out.println(mon.compareTo(wed));*/

        System.out.println(mon.name());             //获取实例名称
        System.out.println(mon.toString());          //调用重写之后的toString方法
    }

}


package com.loaderman.枚举;

public enum Week2 {
    MON("星期一"),TUE("星期二"),WED("星期三");

    private String name;
    private Week2(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }

    public String toString() {
        return name;
    }
}

 

package com.loaderman.枚举;

public enum Week {
    MON,TUE,WED;
}

 

package com.loaderman.枚举;

public enum Week3 {
    MON("星期一"){
        public void show() {
            System.out.println("星期一");
        }
    },TUE("星期二"){
        public void show() {
            System.out.println("星期二");
        }
    },WED("星期三"){
        public void show() {
            System.out.println("星期三");
        }
    };

    private String name;
    private Week3(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }

    public abstract void show();

}