abstract class

[oszc]

hi,all
since we had to override a concrete method in an abstract class ,why java language do not forbid concrete method in abstract class , all using abstract method?

[JosAH]

hi,all
since we had to override a concrete method in an abstract class ,why java language do not forbid concrete method in abstract class , all using abstract method?

An abstract class cannot be directly instantiated (only concrete subclasses thereof can) and it may have abstract methods but it doesn't need to. Of course a subclass needs all of its methods to be implemented, either by itself or by a super class.

kind regards,

Jos

[Tolls]

Not sure I understand the question.
Do you have an example?
Because the way the question sounds at the moment is that if I have:

public abstract class Test {
    public void someMethod() {
    }
}

you seem to think that extending that class will force you to override the someMethod, even though it's not abstract. Which isn't true.