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I have a method on which I need to pass an enum as a parameter.
public <T> T doSomething(SomeEnum operation, Class<T> something); I have several enums and the method is a common one which should work with any enums. What is the correct way to write this method signature to accept any generic enum types? I know that I can use a marker interface to this purpose, but I would like to write it with generic enum signatures. Please advise me on this.
Whats the bad idea with the below one: (It works but I get warnings from IDE saying it is a raw type. I'm not clear about the reason).
public void doSomething(Enum operation); 
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You cannot define enums within methods, but you can define classes, so if you really wish to design your method in this way, you can define an array of your local class object.
Change the signature of the CreateFile method to expect a SupportedPermissions value instead of plain Enum. Show activity on this post. Show activity on this post. First change the method parameter Enum supportedPermissions to SupportedPermissions supportedPermissions .
You can have methods on enums which take parameters. Java enums are not union types like in some other languages.
An enum is defined using the enum keyword, directly inside a namespace, class, or structure. All the constant names can be declared inside the curly brackets and separated by a comma. The following defines an enum for the weekdays. Above, the WeekDays enum declares members in each line separated by a comma.
public <E extends Enum<E>> void doSomething(E operation); EDIT: An example according to your modifications:
public class Main { public enum Day { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY } public <E extends Enum<E>> E doSomething(E operation, Class<E> klazz) { return operation; } public static void main(String[] args) { new Main().doSomething(Day.FRIDAY, Day.class); } } EDIT2:
if you need T and the Enum as separate types, then you'll need:
public <T, E extends Enum<E>> T doSomething(E operation, Class<T> klazz) { If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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