Simple use of JAVA enumeration class

Introduction to Enumeration Classes

The enumeration type is part of the new features in Java 5, it is a special data type. The reason why it is special is that it is both a class type and has more special constraints than class types, but the existence of these constraints also creates the simplicity, safety and convenience of enumeration types.

Simple application of enumeration class

1. The use of constants 

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));
	}
}

print result:

2. Custom function

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));
	}
}

print result:

small expansion

This blog is very rudimentary and can only be used for enumeration understanding. If you want to learn more about enumeration, you can refer to the blog:

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

end