enum inheritance, or something similar

Question

I have a string (which is a message) that I get as input and I need to do one of 4 possible things depending on the string I know that there is eunm.valueOf() option, but I have 4 different enums, each with few possible messages.

looks something like:

public enum first{ONE,TWO,THREE};
public enum second{FOUR,FIVE,SIX};
public enum third{SEVEN,EIGHT,NINE};

public void work(String message){
    //Here I want to compare message string to one of the 3 enums
}

is it possible to do this in one method of the enum? or should I just try to create one, and if I get an exception try the other and so on?

Answer 1

As others have commented, it may be better to think through whether you really need 4 distinct enums.

But if you do, you could have them implement a common interface. Then you can map the input strings to the appropriate enum member, and call its method to accomplish what you want. Something like

public interface SomeInterface {
  void doSomething();
};

public enum First implements SomeInterface {
  ONE,TWO,THREE;
  @Override
  public void doSomething() { ... }
};
...
Map<String, SomeInterface> myMap = new HashMap<String, SomeInterface>();
for (First item : First.values()) {
  myMap.put(item.toString(), item);
}
...

public void work(String message){
  SomeInterface obj = myMap.get(message);
  if (obj != null) {
    obj.doSomething();
  }
}

This assumes that the 4 possible things you want to do correspond to the 4 enums. If not, you can override the method separately for each and any enum member too, e.g.

public enum First implements SomeInterface {
  ONE,
  TWO {
    @Override
    public void doSomething() { // do something specific to TWO }
  },
  THREE;
  @Override
  public void doSomething() { // general solution for all values of First }
};