java:枚举

public enum InfoLight {

    RED,GREEN,BLUE;
}

import java.time.*;
import java.time.format.DateTimeFormatter;
import java.time.temporal.TemporalAdjuster;
import java.time.temporal.TemporalAdjusters;

public class Driver {
    public static void main(String[] args) {

        //获取系统剩余的内存空间
        long begin1 = Runtime.getRuntime().freeMemory();
        //获取系统的当前时间
        long start01 = System.currentTimeMillis();


        for (InfoLight rgb : InfoLight.values()) {
            System.out.println(rgb.name());
        }
        System.out.println("*************************************");
        InfoLight infoLight=InfoLight.BLUE;
        System.out.println(infoLight);
//        enum---->string
        System.out.println(infoLight.name());
//  定义时的序号
        System.out.println(infoLight.ordinal());
//String--->enum
        System.out.println(InfoLight.valueOf("BLUE").name());


        System.out.println(InfoLight.valueOf("wanson"));  //不存在


        System.out.println("\t\t");
        //获取系统剩余的内存空间
        long end2 = Runtime.getRuntime().freeMemory();
        //获取系统的当前时间  单位是毫秒
        long finish02 = System.currentTimeMillis();
        System.out.println("本程序占用内存:" + (begin1 - end2));
        System.out.println("本程序占用时间:" + (finish02 - start01));
    }
}