java枚举enum实用小技巧！不看后悔！！

前言

早就知道枚举了，可却一直不知道合理去应用，今天发现一个小例子，才发现枚举真香！

enum应用

public enum  CountryEnum {
    ONE(1,"齐"),TWO(2,"楚"),THREE(3,"燕"),FOUR(4,"赵"),FIVE(5,"魏"),SIX(6,"韩");


    private Integer retCode;
    private String retMessage;

    CountryEnum(Integer retCode, String retMessage) {
        this.retCode = retCode;
        this.retMessage = retMessage;
    }

    public Integer getRetCode() {
        return retCode;
    }

    public String getRetMessage() {
        return retMessage;
    }

    public static CountryEnum forEach_CountryEnum(int index){
    //代表每个枚举对象ONE TWO
        CountryEnum[] myArray = CountryEnum.values();
        for(CountryEnum ele:myArray){
            if(index == ele.getRetCode()){
                return ele;
            }
        }
        return null;
    }
}

test

public static void main(String[] args) throws InterruptedException {
        CountDownLatch countDownLatch = new CountDownLatch(6);
        for(int i = 1;i <=6;i++){
            new Thread(()->{

                System.out.println(Thread.currentThread().getName() + "\t 国灭亡");
                countDownLatch.countDown();
            },CountryEnum.forEach_CountryEnum(i).getRetMessage()).start();
        }

        countDownLatch.await();
        System.out.println(Thread.currentThread().getName() + "====秦统一");
    }



-----------------
楚	 国灭亡
齐	 国灭亡
燕	 国灭亡
赵	 国灭亡
魏	 国灭亡
韩	 国灭亡
main====秦统一