I want to retrieve the name of the enum type from within the enum type itself:
enum Mammals {
DOG(new Dog()),
CAT(new Cat());
public String alias;
Mammals(AncestorOfDogAndCat a){
this.alias=this.getClass().getName().toLowerCase();
System.out.println(alias);
}
}
When I instance them I get
Main$mammals
Main$mammals
but I want
dog
cat
You can use the name() method on an enum constant to get the name of the enum constant:
enum Mammals {
DOG(),
CAT();
public String alias;
Mammals() {
this.alias = name().toLowerCase();
System.out.println(alias);
}
}
The name() method is something that is automatically added by the compiler on enum types.
name: "Most programmers should use the toString() method in preference to this one, as the toString method may return a more user-friendly name. This method is designed primarily for use in specialized situations where correctness depends on getting the exact name, which will not vary from release to release."
name() method is exactly what you should use if your program depends on it; what toString() returns is more intended for humans to read.Don't use reflection. It's not robust enough. Provide a method which provides this information.
interface Animal
{
String getName();
}
class Dog implements Animal
{
public String getName()
{
return "dog";
}
}
enum Mammals {
DOG(new Dog()),
CAT(new Cat());
public String alias;
Mammals (Animal animal) {
this.alias = animal.getName();
System.out.println(alias);
}
}
Dog class and changes the name to Canine? Seems like a reasonable change - it will compile fine. Only days, weeks, months later will you realise you've broken something.
name method for enums instead of adding a new parameter with a "custom" string value. I mean, with your same argument, if someone refactors the class the enum is still showing the "dog" value and it should now be "canine"getName or the toString method conveniently.enum Mammals {
DOG(new Dog()),
CAT(new Cat());
public String alias;
Mammals(DogOrCat value){
this.alias=name().toLowerCase();
System.out.println(alias);
}
}
or use toString(), which by default is implemented using name.
Using this.getClass() will return the name of the class itself, which is the enum Mammals here. Instead take in a parameter and use getClass on the parameter for your alias.
enum Mammals {
DOG(new Dog()),
CAT(new Cat());
public String alias;
Mammals(Animal an){
this.alias=an.getClass().getName().toLowerCase();
System.out.println(alias);
}
}
where Dog and Cat extend Animal.
name()method but if you need the instance coudn't you simply call to itstoStringmethod? That would make the print dependant to the dog/cat instance instead of the enum type name.