我可以根据其字段的值获取枚举吗？

string enums java

2022-09-01 15:07:11

我想根据其字段值获取特定的枚举。

枚举：

public enum CrimeCategory {
    ASBO ("Anti Social Behaviour"),
    BURG ("Burglary"),
    CRIMDAM ("Criminal Damage And Arson"),
    DRUGS ("Drugs"),
    OTHTHEFT ("Other Theft"),
    PUPDISOR ("Public Disorder And Weapons"),
    ROBBERY ("Robbery"),
    SHOPLIF ("Shoplifting"),
    VEHICLE ("Vehicle Crime"),
    VIOLENT ("Violent Crime"),
    OTHER ("Other Crime");

    private  String category;


    private CrimeCategory (String category) {
        this.category = category;
    }

    public String returnString() {
        return category; 
    }
}

获取新的枚举：

aStringRecivedFromJson = "Anti Social Behaviour"
CrimeCategory crimeCategoryEnum;
crimeCategoryEnum = CrimeCategory.valueOf(aStringRecivedFromJson);

我一直在尝试找出一种方法，以便上述带回一个枚举，以便它可以与其他信息一起存储在一个中。HashMapCrime

预期成果：ASBO

答案 1

作为参考，以下是使用HashMap的替代解决方案：

enum CrimeCategory {
  ASBO("Anti Social Behaviour"),
  BURG("Burglary"),
  CRIMDAM("Criminal Damage And Arson"),
  DRUGS("Drugs"),
  OTHTHEFT("Other Theft"),
  PUPDISOR("Public Disorder And Weapons"),
  ROBBERY("Robbery"),
  SHOPLIF("Shoplifting"),
  VEHICLE("Vehicle Crime"),
  VIOLENT("Violent Crime"),
  OTHER("Other Crime");

  private static final Map<String, CrimeCategory> map = new HashMap<>(values().length, 1);

  static {
    for (CrimeCategory c : values()) map.put(c.category, c);
  }

  private final String category;

  private CrimeCategory(String category) {
    this.category = category;
  }

  public static CrimeCategory of(String name) {
    CrimeCategory result = map.get(name);
    if (result == null) {
      throw new IllegalArgumentException("Invalid category name: " + name);
    }
    return result;
  }
}

答案 2

将静态方法添加到枚举中：CrimeCategory

public static CrimeCategory valueOf(String name) {
    for (CrimeCategory category : values()) {
        if (category.category.equals(name)) {
            return category;
        }
    }    
    throw new IllegalArgumentException(name);
}