Java: instantiating an enum using reflection

Solution 1:

field.set(this, Enum.valueOf((Class<Enum>) field.getType(), value));

• getClass() after getType() should not be called - it returns the class of a Class instance
• You can cast Class<Enum>, to avoid generic problems, because you already know that the Class is an enum

Solution 2:

Alternative solution with no casting

try {
    Method valueOf = field.getType().getMethod("valueOf", String.class);
    Object value = valueOf.invoke(null, param);
    field.set(test, value);
} catch ( ReflectiveOperationException e) {
    // handle error here
}

Solution 3:

You have an extra getClass call, and you have to cast (more specific cast per Bozho):

field.set(test, Enum.valueOf((Class<Enum>) field.getType(), value));

Solution 4:

The accepted answer results in warnings because it uses the raw type Enum instead of Enum<T extends Enum<T>>.

To get around this you need to use a generic method like this:

@SuppressWarnings("unchecked")
private <T extends Enum<T>> T createEnumInstance(String name, Type type) {
  return Enum.valueOf((Class<T>) type, name);
}

Call it like this:

Enum<?> enum = createEnumInstance(name, field.getType());
field.set(this, enum);