JavaSE-枚舉類

package com.btp.t4;
/*
 * 一.枚舉類
 * 1.如何自定義枚舉類
 * 2.如何使用enum關鍵字定義枚舉類
 *     >常用的方法:values()，valueOf(String name)
 *     >如何讓枚舉類實作接口：讓不同的枚舉類對象調用被重寫的抽象方法，執行的效果不同。（相當于讓每個對象重寫抽象方法）
 */
public class TestSeason {

	public static void main(String[] args){
		Season spring=Season.SPRING;
		System.out.println(spring);
		spring.show();
		System.out.println(spring.getSeasonDesc());
		
		//1.values()
		Season1[] season=Season1.values();
		for(Object obj:season)
		{
			System.out.println(obj);
		}
		System.out.println();
		//2.valueOf(String name):要求傳入的形參是枚舉類對象的名字，否則報異常
		String str="SPRING";
		Season1 sea=Season1.valueOf(str);
		System.out.println(sea);
		System.out.println();
		
		sea.show();
		
		System.out.println();
		//Thread類的内部類State是一個枚舉類
		Thread.State[] states=Thread.State.values();
		for(Object obj:states)
		{
			System.out.println(obj);
		}
		
	}
}

//自定義枚舉類:如果隻有一個對象，則是單例模式
class Season{
	//1.提供類的屬性，聲明為private final
	private final String seasonName;
	private final String seasonDesc;
	//2.聲明為final的屬性，在私有化構造器中初始化
	private Season(String seasonName,String seasonDesc){
		this.seasonName=seasonName;
		this.seasonDesc=seasonDesc;
	}
	//3.通過公共方法調用
	public String getSeasonName() {
		return seasonName;
	}
	public String getSeasonDesc() {
		return seasonDesc;
	}
	//4.建立枚舉類的對象:将類的對象聲明為public static final
	public static final Season SPRING=new Season("spring","春暖花開");
	public static final Season SUMMER=new Season("summer","夏日炎炎");
	public static final Season AUTUMN=new Season("autumn","秋高氣爽");
	public static final Season WINTER=new Season("winter","白雪皚皚");
	
	@Override
	public String toString() {
		return "Season [seasonName=" + seasonName + ", seasonDesc=" + seasonDesc + "]";
	}
	public void show(){
		System.out.println("這是一個"+this.getSeasonName()+"季節！");
	}
}

//接口info
interface info{
	void show();
}


//用enum關鍵字定義枚舉類
enum Season1 implements info{
	//成員要寫在最前面
	//讓不同的枚舉類對象調用被重寫的抽象方法，執行的效果不同。（相當于讓每個對象重寫抽象方法）
	SPRING("spring","春暖花開"){
		public void show(){
			System.out.println("春天在哪裡？");
		}
	},
	SUMMER("summer","夏日炎炎"){
		public void show(){
			System.out.println("生如夏花");
		}
	},
	AUTUMN("autumn","秋高氣爽"){
		public void show(){
			System.out.println("秋天是分手的季節");
		}
	},
	WINTER("winter","白雪皚皚"){
		public void show(){
			System.out.println("冬天裡的一把火火");
		}
	};
	private final String seasonName;
	private final String seasonDesc;
	private Season1(String seasonName,String seasonDesc){
		this.seasonName=seasonName;
		this.seasonDesc=seasonDesc;
	}
	@Override
	public String toString() {
		return "Season [seasonName=" + seasonName + ", seasonDesc=" + seasonDesc + "]";
	}
	
//	public void show() {
//		// TODO 自動生成的方法存根
//		System.out.println("這是一個季節！");
//	}
	
}
           

　　

轉載于:https://www.cnblogs.com/a842297171/p/5170344.html