当枚举类型用在switch语句中时,语法有一点点特别。看例子:
package other;
import basic.Day;
public class SwitchTest
{
    public static void main(String [] args)
    {
        int FRIDAY = 5;
        System.out.println(FRIDAY);
        
        Day today = Day.SATURDAY;
        switch(today)
        {
        case FRIDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case SATURDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case SUNDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case MONDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case TUESDAT:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case WEDNESDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        case THURSDAY:
            System.out.println("Today is " + today.toString().toLowerCase());
            break;
        default:
            System.out.println("otherday");
        }
    }
}
注意在case标签中,Day不出现,即case Day.FRIDAY是不合法的。而在其他地方出现时则必须用Day.FRIDAY