Java Enum类(常用方法详解和演示)

方便日后回顾

public class EnumTestDemo02 {
    public static void main(String[] args) {
        
        switch (Season.valueOf("SUMMER")) {
            case SPRING:
                System.out.println("春天");
                break;
            case SUMMER:
                System.out.println("夏天");
                break;
            case AUTUMN:
                System.out.println("秋天");
                break;
            case WINTER:
                System.out.println("冬天");
                break;
            default:
                System.out.println("没有季节的一天~~~");
        }
        System.out.println(Season.AUTUMN);//AUTUMN("不是字符串类型")
        System.out.println(Season.valueOf("AUTUMN"));//AUTUMN("不是字符串类型")
        System.out.println(Season.AUTUMN.name());//AUTUMN("字符串类型")
        //补充：2种方式判断是否是字符串类型
        //1.instanceof
        System.out.println(Season.AUTUMN instanceof Season);//true,说明是枚举类型
        System.out.println(Season.valueOf("AUTUMN") instanceof Season);//true,说明是枚举类型
        System.out.println(Season.AUTUMN.name() instanceof String);//true,说明是字符串类型
        //2.反射方式
        try {
			//这里只是判断枚举类中的AUTUMN枚举的类型
           System.out.println(Season.class.getDeclaredField("AUTUMN").getType());//class Season
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }
        System.out.println(Season.AUTUMN.name());//AUTUMN
        System.out.println(Season.AUTUMN.description());//秋天
        System.out.println(Season.AUTUMN.month());//789
        Season winter = Season.WINTER;
        System.out.println(winter);//WINTER

        Season[] values = Season.values();
        for (int i = 0; i < values.length; i++) {
            
            System.out.println(values[i]);
        }

        //遍历循环
        for (Season season : Season.values()) {
            
            System.out.println("season: "+season);
            System.out.println("season.name():"+season.name()+" 下标: "+ season.ordinal());
        }
    }
}

Season 枚举类

public enum Season {
    
    SPRING("春天",123),
    SUMMER("夏天",456),
    AUTUMN("秋天",789),
    WINTER("冬天",101112);
    private final String description;
    private Integer month;
    Season(String description, Integer month) {
        this.description = description;
        this.month = month;
    }

    public Integer month(){
        return month;
    }

    public String description(){
        return description;
    }
}