JAVA枚举类的简单使用

枚举类简介

枚举类型是Java 5中新增特性的一部分，它是一种特殊的数据类型。之所以特殊是因为它既是一种类(class)类型却又比类类型多了些特殊的约束，但是这些约束的存在也造就了枚举类型的简洁性、安全性以及便捷性。

枚举类的简单应用

1、常量的使用 

enum Day {
    MON, TUE, WED,
    THU, FRI, SAT, SUN
}

public class Mian01 {

	public static void main(String[] args) {
		// 直接引用
		Day day01 = Day.MON;
		Day day02 = Day.THU;
		Day day03 = Day.SUN;

		System.out.println("-----------------toString()-------------------");
		// 1、toString
		System.out.println(day01.toString());
		System.out.println(day02.toString());
		System.out.println(day03.toString());

		System.out.println("-----------------ordinal()-------------------");
		// 2、ordinal()
		System.out.println(day01.ordinal());
		System.out.println(day02.ordinal());
		System.out.println(day03.ordinal());

		System.out.println("------------------name()--------------------");
		// 3、name()
		System.out.println(day01.name());
		System.out.println(day02.name());
		System.out.println(day03.name());

		System.out.println("-----------------compareTo()------------------");
		// 4、compareTo()
		System.out.println(day01.compareTo(day01));
		System.out.println(day01.compareTo(day02));
		System.out.println(day03.compareTo(day01));
	}
}

打印结果：

2、自定义函数

public enum Day {
	MON("星期一", 1), TUE("星期二", 2), WED("星期三", 3),
    THU("星期四", 4), FRI("星期五", 5), SAT("星期六", 6), SUN("星期日", 7);
	
	private String chineseName;
	private int number;
	
	private Day(String chineseName, int number){
		this.chineseName = chineseName;
		this.number = number;
	}
	
	//重写toSting()
	@Override
	public String toString() {
		return "chineseName:"+chineseName+" & number:"+number;
	}

	public String getChineseName() {
		return chineseName;
	}

	public void setChineseName(String chineseName) {
		this.chineseName = chineseName;
	}

	public int getNumber() {
		return number;
	}

	public void setNumber(int number) {
		this.number = number;
	}
}

public class Mian01 {

	public static void main(String[] args) {
		// 直接引用
		Day day01 = Day.MON;
		Day day02 = Day.THU;
		Day day03 = Day.SUN;

		System.out.println("-----------------toString()-------------------");
		// 1、toString
		System.out.println(day01.toString());
		System.out.println(day02.toString());
		System.out.println(day03.toString());

		System.out.println("-----------------ordinal()-------------------");
		// 2、ordinal()
		System.out.println(day01.ordinal());
		System.out.println(day02.ordinal());
		System.out.println(day03.ordinal());

		System.out.println("------------------name()--------------------");
		// 3、name()
		System.out.println(day01.name());
		System.out.println(day02.name());
		System.out.println(day03.name());

		System.out.println("-----------------compareTo()------------------");
		// 4、compareTo()
		System.out.println(day01.compareTo(day01));
		System.out.println(day01.compareTo(day02));
		System.out.println(day03.compareTo(day01));
	}
}

打印结果：

小小的拓展

本篇blog是非常初级的，仅仅可用于枚举的了解。如果想深入的了解枚举，可参考blog：

http://blog.csdn.net/javazejian/article/details/71333103

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