Can we use static method in an abstract class?

java interface static abstract
Neha Gupta picture Neha Gupta · Jul 1, 2013 · Viewed 91.7k times · Source

In Java Programming, Can we call a static method of an abstract class?
Yes I know we can't use static with a method of an abstract class. but I want to know why.. ?

Answer

Russell Zahniser picture Russell Zahniser · Jul 1, 2013

In Java you can have a static method in an abstract class:

abstract class Foo {
   static void bar() { }
}

This is allowed because that method can be called directly, even if you do not have an instance of the abstract class:

Foo.bar();

However, for the same reason, you can't declare a static method to be abstract. Normally, the compiler can guarantee that an abstract method will have a real implementation any time that it is called, because you can't create an instance of an abstract class. But since a static method can be called directly, making it abstract would make it possible to call an undefined method.

abstract class Foo {
   abstract static void bar();
}

// Calling a method with no body!
Foo.bar();

In an interface, all methods are implicitly abstract. This is why an interface cannot declare a static method. (There's no architectural reason why an interface couldn't have a static method, but I suspect the writers of the JLS felt that that would encourage misuse of interfaces)

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