java 自定义可继承枚举Enum的案例

public class AbstractEnum { private static final Map<String, AbstractEnum> nameEnumMap = new ConcurrentHashMap<>(); @Getter protected String name; protected AbstractEnum () { } protected AbstractEnum(String name) { this.name = name; if (!nameEnumMap.containsKey(name)) { nameEnumMap.put(name, this); } } public boolean equals(AbstractEnum abstractEnum) { return this.name == null || abstractEnum == null ? false : this.name.equals(abstractEnum.getName()); } public String toString() { return this.name; } public static AbstractEnum valueOf(String name) { if (name == null) throw new NullPointerException('Name is null'); AbstractEnum result = nameEnumMap.get(name); if (result != null) { return result; } throw new IllegalArgumentException( 'No enum constant exists, name is.' + name); } public static void init() { } }二、实际继承enum，与enum使用方法一致

public class TypeEnum extends AbstractEnum { private static final Map<String, TypeEnum> nameEnumMap = new ConcurrentHashMap<>(); protected TypeEnum(String name) { super(name); if (!nameEnumMap.containsKey(name)) { nameEnumMap.put(name, this); } } public static TypeEnum valueOf(String name) { if (name == null) throw new NullPointerException('Name is null'); TypeEnum result = nameEnumMap.get(name); if (result != null) { return result; } throw new IllegalArgumentException( 'No enum constant exists, name is.' + name); } public static final TypeEnum TYPE_ONE = new TypeEnum('TYPE_ONE');}三、可继续继承枚举，进行枚举分类。

补充：Java中自定义枚举（Enum）项的值,可设置为指定的值

package base.lang;/** * ClassName: StateEnum * @Description: TODO * @author fuming * @date 2016年11月27日 */public enum StateEnum{//添加枚举的指定常量online(10),offline(20);//必须增加一个构造函数,变量,得到该变量的值private int mState=0;private StateEnum(int value){mState=value;}/*** @return 枚举变量实际返回值*/ public int getState() { return mState; } }二、示例

//enum StateEnum orderState=StateEnum.offline; //orderState=StateEnum.online; System.out.println('state='+ orderState.getState()); 三、打印结果

state=20 //测试正常

以上为个人经验，希望能给大家一个参考，也希望大家多多支持好吧啦网。如有错误或未考虑完全的地方，望不吝赐教。