Java Enum embed the class in the feild

I have one java enum class called Country for which I have below code :

public enum Country {
	
	AFGHANISTAN("Afghanistan","AF","AFG",004, RegionAfghanistan.class),
	ALBANIA("Albania","AL","ALB",8, RegionAlbania.class);
    .......
    Some methods and constructor.
}

So you can see in the last field I have embedded the class in the enum fields. Each of these region is enum class as below.

public enum RegionAfghanistan {

	BADAKHSHAN("Badakhshān", "AF-BDS*", CountryCategory.PROVINCE),
	BAGHLAN("Baghlān", "AF-BGL*", CountryCategory.PROVINCE),
	BALKH("Balkh", "AF-BAL*", CountryCategory.PROVINCE),
	BADGHIS("Bādghīs", "AF-BDG*", CountryCategory.PROVINCE),
	BAMYAN("Bāmyān", "AF-BAM*", CountryCategory.PROVINCE),
	DAYKUNDI("Dāykundī", "AF-DAY*", CountryCategory.PROVINCE),
    ......
    Some methods and feilds.

Now Suppose I am given Region: Badakhshān Country: Afghanistan as a String. First I have method which gives me Country.AFGHANISTAN from the "Afghanistan", So that, is fine.
I also get a class from the Country.AFGHANISTAN i.e. class com.****.core.location.RegionAfghanistan but I would like to get RegionAfghanistan.BADAKHSHAN from the given region "Badakhshān".
Could you please help me how to achieve this using the java enums. Hope you understand what I want to achieve using this.

I have used the following code

Class c = Country.AFGHANISTAN.getRegion(); 
Method methodname = c.getMethod("getRegionAfghanistanBySubdivisionName", String.class); 
System.out.println(methodname.invoke(c, "Badakhshān")); 

I get Country.AFGHANISTAN from string "Afghanistan", then I get the class and I invoke a method in class passing the region "Badakhshān" and I get the right value but I am not sure if I am doing it the right way or there is another better way to do it.

I would really want a help if this is right approach or there is better way to do it....Thank you so much for your help.

You could add a method to the RegionAfghanistan (and other region enumerations) that lets you look up a region by its name. It could look like:

    public static RegionAfghanistan getByName(String name) {
        for (RegionAfghanistan value : values()) {
            if (value.name.equals(name)) {
                return value;
            }
        }
        throw new IllegalArgumentException("Not a region: " + name);
    }

You can call this method via reflection given the Class object for RegionAfghanistan:

Class<RegionAfghanistan> regionAfghanistanClass = RegionAfghanistan.class;

// Look up method
Method getByName = regionAfghanistanClass.getMethod("getByName", String.class);

// Call it. It's a static method, so pass in "null"
RegionAfghanistan badakhshān = (RegionAfghanistan) getByName.invoke(null, "Badakhshān");

Another approach which links country enum to its regions values, you would need to improve getRegions call to match on the text labels rather than toUpperCase I used:

public enum RegionAfghanistan {
    BALKH, BAGHLAN;
}
public enum RegionUK {
    WALES, ENGLAND;
}
public enum Country {
    AFGHANISTAN(RegionAfghanistan.values()),
    UK(RegionUK.values());

    private Enum<?>[] regions;
    <T extends Enum<T>> Country(T[] values) {
        this.regions = values;
    }
    <T extends Enum<T>> T getRegion(String name) {
        return Enum.valueOf((Class<T>) regions[0].getClass(), name.toUpperCase());
    }
}
public static void main(String[] args) {
    System.out.println(Country.AFGHANISTAN.getRegion("Balkh"));
    System.out.println(Country.UK.getRegion("Wales"));
}

Experimented a bit, and figured out you can also do it by using a Region interface and a abtract method in the Country enum. This setup requires a lot of repeated code to tell it which Region enum to use though.

Region interface:

public interface Region{}

RegionUSA Enum:

public enum RegionUSA implements Region
{
  WASHINGTON, FLORIDA;
}

RegionCanada Enum:

public enum RegionCanada implements Region
{
  QUEBEC, ALBERTA;
}

RegionFrance Enum:

public enum RegionFrance implements Region
{
  NORMANDY, BERRY;
}

Country Enum:

public enum Country
{
  USA
  {
    @Override
    public Region getRegion(String region)
    {
      return RegionUSA.valueOf(region.toUpperCase());
    }
  }, 
  CANADA
  {
    @Override
    public Region getRegion(String region)
    {
      return RegionCanada.valueOf(region.toUpperCase());
    }
  }, 
  FRANCE
  {
    @Override
    public Region getRegion(String region)
    {
      return RegionFrance.valueOf(region.toUpperCase());
    }
  };
  
  public abstract Region getRegion(String region);
}

Main Class:

public class TestEnums
{
  public static void main(String[] args) 
  {
    System.out.println(Country.CANADA.getRegion("Alberta"));
    System.out.println(Country.USA.getRegion("Washington"));
    System.out.println(Country.FRANCE.getRegion("Normandy"));
  }
}