枚舉類的引入:java
解決類型不安全,業務不明確!安全
枚舉的定義:函數
枚舉主要用來表示事務固定的類型。this
程序示例:spa
enum Weekday{ //定義枚舉類型表示一週的七天 SUN, MON, Tues, WEDNES, THUR, FIR, SATUR; } class Employ{ private String name; //員工姓名 private Weekday restday; //員工的休息日 public void setName(String name) { this.name = name; } public String getName() { return name; } public void setRestday(Weekday restday) { this.restday = restday; } public Weekday getRestday() { return restday; } public void restTime(Weekday restday,String name){ if (restday==Weekday.SUN||restday==Weekday.SATUR){ System.out.println(name+"在週末休息!"); }else{ System.out.println(name+"在周內休息!"); } } } public class Enum { public static void main(String[] args) { Employ E1= new Employ(); Employ E2= new Employ(); Weekday today= Weekday.FIR; E1.setRestday(today); E1.setName("Tom"); System.out.println(E1.getName()+"的休息日是:"+today); E1.restTime(today,E1.getName()); System.out.println("\n"+"**********************"); E2.setRestday(Weekday.SATUR); E2.setName("Jim"); System.out.println(E2.getName()+"的休息日是:"+E2.getRestday()); E2.restTime(E2.getRestday(),E2.getName()); System.out.println("\n"+"*******枚舉類型的經常使用函數*******"); System.out.println(today.ordinal()); //對象的序號(從0開始) System.out.println(today.name()); //對象的名稱 System.out.println(today.toString()); //對象的名稱 System.out.println(today.getClass()); //對象的類 } }
程序示例運行結果:rest
Tom的休息日是:FIR Tom在周內休息! ********************** Jim的休息日是:SATUR Jim在週末休息! *******枚舉類型的經常使用函數******* 5 FIR FIR class mypro01.Weekday
枚舉的使用code