策略枚举

package common;

public enum PayrollDay {

    MONDAY(PayType.WEEKDAY), TUESDAY(PayType.WEEKDAY), WEDNESDAY(
	    PayType.WEEKDAY), THURSDAY(PayType.WEEKDAY), FRIDAY(PayType.WEEKDAY), SATURDAY(
	    PayType.WEEKDAY), SUNDAY(PayType.WEEKDAY);
    private final PayType type;
    private PayrollDay(PayType type) {
	this.type = type;
    }
    double pay(double hours,double rate) {
	return type.pay(hours, rate);
    }
    // 枚举策略
    private enum PayType {
	WEEKDAY {
	    double overtimePay(double hours, double rate) {
		return hours <= HOURS_PER_SHIFT ? 0 : (hours - HOURS_PER_SHIFT)
			* rate / 2;
	    }
	},
	WEEEND {
	    double overtimePay(double hours, double rate) {
		return hours * rate / 2;
	    }
	};
	private static final int HOURS_PER_SHIFT = 8;

	abstract double overtimePay(double hours, double rate);

	double pay(double hours, double rate) {
	    double basePay = hours * rate;
	    return basePay + overtimePay(hours, rate);
	}
    }
}