public enum State {
    Normal("正常态", 1), Update("已更新", 2), Deleted("已删除", 3), Fired("已屏蔽", 4);
    // 成员变量
    private String name;
    private int index;

    // 构造方法，注意：构造方法不能为public，因为enum并不可以被实例化
    private State(String name, int index) {
      this.name = name;
      this.index = index;
    }

    // 普通方法
    public static String getName(int index) {
      for (State c : State .values()) {
        if (c.getIndex() == index) {
          return c.name;
        }
      }
      return null;
    }

    // get set 方法
    public String getName() {
      return name;
    }

    public void setName(String name) {
      this.name = name;
    }

    public int getIndex() {
      return index;
    }

    public void setIndex(int index) {
      this.index = index;
    }
  }

public static final int normalState = 1;
private static final int updateState = 2;

public enum State { 
 Normal, Update, Deleted, Fired
}

public interface ICanReadState {
    void read();

    String getState();
}

  public enum State implements ICanReadState {
    Normal("正常态", 1), Update("已更新", 2), Deleted("已删除", 3), Fired("已屏蔽", 4);

    private String name;
    private int index;

    private State(String name, int index) {
      this.name = name;
      this.index = index;
    }

    // 接口方法1

    @Override
    public String getState() {
      return this.name;
    }

    // 接口方法2
    @Override
    public void read() {
      System.out.println(this.index + ":" + this.name);
    }
  }

public enum SqlTypeEnum {
  INSERT , 
  UPDATE ,
  DELETE ,
  SELECT
}

String token = "select";
SqlTypeEnum sqlTypeEnum = SqlTypeEnum.valueOf(token.toUpperCase());

switch(sqlTypeEnum) {
 case INSERT:处理insert逻辑;break;
 case DELETE:处理delete逻辑;break;
 ....
}

public enum UserOptionEnum {
  SAVE_USER,
  GET_USER_BY_ID,
  GET_USER_LIST,
  DELETE_USER_BY_ID
}

public static String convertDbStyleToJavaStyle(String dbStyleString , boolean firstUpper) {
    dbStyleString = dbStyleString.toLowerCase();
    String []tokens = dbStyleString.split("_");
    StringBuilder stringBuilder = new StringBuilder(128);
    int length = 0;
    for(String token : tokens) {
      if(StringUtils.isNotBlank(token)) {
        if(length == 0 && !firstUpper) {
          stringBuilder.append(token);
        }else {
          char c = token.charAt(0);
          if(c >= 'a' || c <= 'z') c = (char)(c - 32);
          stringBuilder.append(c);
          stringBuilder.append(token.substring(1));
        }
      }
      ++length;
    }
    return stringBuilder.toString();
  }

public static String convertDbStyleToJavaLocalStyle(String dbStyleString) {
    return convertDbStyleToJavaStyle(dbStyleString , false);
  }

public enum UserOptionEnum {
  SAVE_USER,
  GET_USER_BY_ID,
  GET_USER_LIST,
  DELETE_USER_BY_ID;
 
  private final static Map<String , UserOptionEnum> ENUM_MAP = new HashMap<String, UserOptionEnum>(64);
 
  static {
    for(UserOptionEnum v : values()) {
      ENUM_MAP.put(v.toString() , v); 
    }
  }
 
  public staticUserOptionEnum fromString(String v) {
    UserOptionEnum userOptionEnum = ENUM_MAP.get(v);
    return userOptionEnum == null ? DEFAULT :userOptionEnum;
  }
 
  public String toString() {
    String stringValue = super.toString();
    return StringUtil.convertDbStyleToJavaLocalStyle(stringValue);
  }
}

String event = "saveUser";//假如这里得到参数
UserOptionEnum enum = UserOptionEnum.fromString(event);

public enum SqlTypeEnum {
  INSERT("insert into"),
  DELETE("delete from")
  ......省略;
 
  private String name;//定义自定义的变量
 
  private SqlTypeEnum(String name) {
   this.name = name;
  }
 
  public String getName() {
    return name;
  }
 
  public String toString() {
    return name + " 我靠";//重写toString方法
 }
 //一般不推荐
 public void setName(String name) {
    this.name = name;
 }
}

SqlTypeEnum sqlTypeEnum = SqlTypeEnum.valueOf("INSERT");
System.out.println(sqlTypeEnum);
System.out.println(sqlTypeEnum.getName());

sqlTypeEnum.setName("我靠");

SqlTypeEnum sqlTypeEnum = SqlTypeEnum.valueOf("INSERT");
System.out.println(sqlTypeEnum);
System.out.println(sqlTypeEnum.getName());