How do I "valueOf" an enum given a class name?
Lets say I have a simple Enum called Animal defined as:
public enum Animal {
CAT, DOG
}
and I have a method like:
private static Object valueOf(String value, Class<?> classType) {
if (classType == String.class) {
return value;
}
if (classType == Integer.class) {
return Integer.parseInt(value);
}
if (classType == Long.class) {
return Long.parseLong(value);
}
if (classType == Boolean.class) {
return Boolean.parseBoolean(value);
开发者_如何学JAVA }
// Enum resolution here
}
What can I put inside this method to return an instance of my enum where the value is of the classType?
I have looked at trying:
if (classType == Enum.class) {
return Enum.valueOf((Class<Enum>)classType, value);
}
But that doesn't work.
Your classType
isn't Enum
, it's Animal
. So,
if (classType.isEnum()) {
return Enum.valueOf(classType, value);
}
should work. Additionally, you ought to use equals()
rather than ==
for comparing the class instances (although ==
will work in practice, if there's just one classloader around).
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