Java中枚举类的用法示例详解

enum Color 
{ 
    RED, GREEN, BLUE; 
} 

/**
 * java枚举
 */
public class Enum {
    public static void main(String[] args) {
        System.out.println(Season.SPRING);
        System.out.println(Season.SUMMER);
        System.out.println(Season.AUTUMN);
        System.out.println(Season.WINTER);
    }
}

// 定义的枚举类
enum Season {
    // 枚举定义的常量对象必须在最前面
    SPRING("春天","万物复苏"),
    SUMMER("夏天","烈日炎炎"),
    AUTUMN("秋天","硕果累累"),
    WINTER("冬天","寒冷刺骨");

    private String name;
    private String desc;

    private Season(String name, String desc) {
        this.name = name;
        this.desc = desc;
    }

    public String getName() {
        return name;
    }

    public String getDesc() {
        return desc;
    }

    @Override
    public String toString() {
        return "Season{" +
                "name='" + name + '\'' +
                ", desc='" + desc + '\'' +
                '}';
    }
}

// 枚举定义的常量对象必须在最前面
SPRING("春天", "万物复苏"),
SUMMER("夏天", "烈日炎炎"),
AUTUMN("秋天", "硕果累累"),
WINTER("冬天", "寒冷刺骨"),
Other, Shit;

Season() {
}

private Season(String name, String desc) {
    this.name = name;
    this.desc = desc;
}

/**
 * 枚举类方法
 */
public class EnumMethod {
    public static void main(String[] args) {
        Season autumn = Season.AUTUMN;
        // 获取当前枚举对象的名称
        System.out.println(autumn.name());

        // 输出该枚举对象的次序，从0开始
        System.out.println(autumn.ordinal());

        // 返回所有的枚举对象
        Season[] values = Season.values();
        for (Season value : values) {
            System.out.println(value);
        }

        // 将字符串转化为枚举对象,要求字符串必须为已有的常量名，否则会爆出一个异常
        Season autumn1 = Season.valueOf("AUTUMN");
        System.out.println(autumn1);

        // 比较两个枚举常量，比较的就是编号
        // AUTUMN的编号减去SUMMER的编号
        System.out.println(Season.AUTUMN.compareTo(Season.SUMMER));
    }
}