Enum类的方法如下图所示

我们来看一下几个常用的方法：

values()方法：返回枚举类型的对象数组。该方法可以很方便地遍历所有的枚举值。

valueOf(String str)：可以把一个字符串转为对应的枚举类对象。要求字符串必须是枚举类对象的“名字”。如不是，会有运行时异常：IllegalArgumentException。

toString()：返回当前枚举类对象常量的名称

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举例说明：

values()方法：返回枚举类型的对象数组。该方法可以很方便地遍历所有的枚举值。

public class SeasonTest01 {
    public static void main(String[] args) {
        Season1 summer = Season1.SUMMER;
        //toString():
        System.out.println(summer);

        //System.out.println(Season1.class.getSuperclass());

        System.out.println("===================================");
        //values():
        Season1[] values = Season1.values();
        for (int i = 0; i < values.length; i++) {
            System.out.println(values[i]);
        }
    }
}
//使用enum关键词枚举类
enum Season1{
    //1.提供当前枚举类的多个对象,多个对象之间用“,“隔开，末尾对象";"结束
    SPRING ("春天","春暖花开"),
    SUMMER ("夏天","夏日炎炎"),
    AUTUMN ("秋天","秋高气爽"),
    WINTER ("冬天","冰天雪地");


    //2.声明Season对象的属性:private final修饰
    private final String seasonName;
    private final String seasonDesc;

    //3.私有化类的构造器,并给对象属性赋值
    private Season1(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }


    //4.其他诉求1：获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

    //4.其他诉求1：提供toString()
//    @Override
//    public String toString() {
//        return "Season1{" +
//                "seasonName='" + seasonName + '\'' +
//                ", seasonDesc='" + seasonDesc + '\'' +
//                '}';
//    }
}

运行结果如下：

我们再以线程的状态为例：

public class SeasonTest01 {
    public static void main(String[] args) {
        Season1 summer = Season1.SUMMER;
        //toString():
        System.out.println(summer);

        //System.out.println(Season1.class.getSuperclass());

        System.out.println("===================================");
        //values():
        Season1[] values = Season1.values();
        for (int i = 0; i < values.length; i++) {
            System.out.println(values[i]);
        }

        System.out.println("===============================");
        Thread.State[] values1 = Thread.State.values();
        for (int i = 0; i < values1.length; i++) {
            System.out.println(values1[i]);
        }
    }
}
//使用enum关键词枚举类
enum Season1{
    //1.提供当前枚举类的多个对象,多个对象之间用“,“隔开，末尾对象";"结束
    SPRING ("春天","春暖花开"),
    SUMMER ("夏天","夏日炎炎"),
    AUTUMN ("秋天","秋高气爽"),
    WINTER ("冬天","冰天雪地");


    //2.声明Season对象的属性:private final修饰
    private final String seasonName;
    private final String seasonDesc;

    //3.私有化类的构造器,并给对象属性赋值
    private Season1(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }


    //4.其他诉求1：获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

    //4.其他诉求1：提供toString()
//    @Override
//    public String toString() {
//        return "Season1{" +
//                "seasonName='" + seasonName + '\'' +
//                ", seasonDesc='" + seasonDesc + '\'' +
//                '}';
//    }
}

运行结果如下图：

public class SeasonTest01 {
    public static void main(String[] args) {
        Season1 summer = Season1.SUMMER;
        //toString():
        System.out.println(summer);

        //System.out.println(Season1.class.getSuperclass());

        System.out.println("===================================");
        //values():
        Season1[] values = Season1.values();
        for (int i = 0; i < values.length; i++) {
            System.out.println(values[i]);
        }

        System.out.println("===============================");
        Thread.State[] values1 = Thread.State.values();
        for (int i = 0; i < values1.length; i++) {
            System.out.println(values1[i]);
        }

        System.out.println("=======================================");
        //valuesOf(String objName):返回枚举类中对象名是objName的对象
        Season1 winter = Season1.valueOf("WINTER");
        System.out.println(winter);
    }
}
//使用enum关键词枚举类
enum Season1{
    //1.提供当前枚举类的多个对象,多个对象之间用“,“隔开，末尾对象";"结束
    SPRING ("春天","春暖花开"),
    SUMMER ("夏天","夏日炎炎"),
    AUTUMN ("秋天","秋高气爽"),
    WINTER ("冬天","冰天雪地");


    //2.声明Season对象的属性:private final修饰
    private final String seasonName;
    private final String seasonDesc;

    //3.私有化类的构造器,并给对象属性赋值
    private Season1(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }


    //4.其他诉求1：获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

    //4.其他诉求1：提供toString()
//    @Override
//    public String toString() {
//        return "Season1{" +
//                "seasonName='" + seasonName + '\'' +
//                ", seasonDesc='" + seasonDesc + '\'' +
//                '}';
//    }
}

运行结果如下：

假如我们将括号里的WINTER写错了写成了WINTER1.那就找不到了。运行结果如下：

我们可以发现如果没有objName的枚举类对象，则抛异常：IllegalArgumentException

感谢观看！！!

【Java枚举类】Enum类的主要方法

Enum类的方法如下图所示

举例说明：

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