匿名内部类抽象实现枚举

/* 星期天： Sun.=Sunday 星期一： Mon.=Monday 星期二： Tues.=Tuesday 星期三： Wed.=Wednesday  星期四： Thur.=Thursday 星期五： Fri.=Friday 星期六： Sat.=Saturday  */public abstract class WeekDayAbstract {// 构造函数私有化 不可以在new实例对象private WeekDayAbstract() {}// 采用匿名内部类的实现方式public static final WeekDayAbstract SUNDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return MONDAY;}};public static final WeekDayAbstract MONDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return TUESDAY;}};public static final WeekDayAbstract TUESDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return WEDDAY;}};public static final WeekDayAbstract WEDDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return THURDAY;}};public static final WeekDayAbstract THURDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return FRIDAY;}};public static final WeekDayAbstract FRIDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return SATDAY;}};public static final WeekDayAbstract SATDAY = new WeekDayAbstract() {public WeekDayAbstract NextDay() {return SUNDAY;}};// 定义NextDay（）方法public abstract WeekDayAbstract NextDay();public String toString() { // 重写ToString方法return this == MONDAY ? "星期一" : this == TUESDAY ? "星期二": this == WEDDAY ? "星期三" : this == THURDAY ? "星期四": this == FRIDAY ? "星期五" : this == SATDAY ? "星期六": "星期日";}}