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Can abstract class can have final methods?

Can abstract class can have final methods?

However, an abstract class can have a final method. This final method is treated like a normal method with a body which cannot be overridden.

Can we have a method which is both abstract and final?

No, Abstract method cannot be declared as final. This is because, abstract method has to be overridden to provide implementation. If it is declared as final, it cannot be overridden.

Can an abstract class be final in Java?

If you declare a class abstract, to use it, you must extend it and if you declare a class final you cannot extend it, since both contradict with each other you cannot declare a class both abstract and final if you do so a compile time error will be generated.

Can a method be abstract?

A method without body (no implementation) is known as abstract method. A method must always be declared in an abstract class, or in other words you can say that if a class has an abstract method, it should be declared abstract as well.

Can we override the final method?

Can We Override a Final Method? No, the Methods that are declared as final cannot be Overridden or hidden. Methods are declared final in java to prevent subclasses from Overriding them and changing their behavior, the reason this works is discussed at the end of this article.

Which method Cannot be overridden?

A method declared final cannot be overridden. A method declared static cannot be overridden but can be re-declared. If a method cannot be inherited, then it cannot be overridden. A subclass within the same package as the instance’s superclass can override any superclass method that is not declared private or final.

Can an interface be final?

Making an interface final. If you make a method final you cannot override it and, if you make a variable final you cannot modify it. If you make an interface final, you cannot implement its methods which defies the very purpose of the interfaces. Therefore, you cannot make an interface final in Java.

Can abstract method be private?

If a method of a class is private, you cannot access it outside the current class, not even from the child classes of it. But, incase of an abstract method, you cannot use it from the same class, you need to override it from subclass and use. Therefore, the abstract method cannot be private.

Can a constructor be final?

No, a constructor can’t be made final. A final method cannot be overridden by any subclasses. But, in inheritance sub class inherits the members of a super class except constructors. In other words, constructors cannot be inherited in Java therefore, there is no need to write final before constructors.

Can a final class contain an abstract method?

Hence, a final class cannot contain abstract methods whereas an abstract class can contain a final method. Below is an example which demonstrates the combination of abstract and final classes. Clearly, this implementation is invalid because a final class cannot have an abstract method.

Can you declare an abstract method before a method in Java?

Therefore, you cannot use abstract and final together before a method. If, you still try to declare an abstract method final a compile time error is generated saying “illegal combination of modifiers: abstract and final”. In the following Java program, we are trying to declare an abstract method final.

Is it illegal to put an abstract method in a subclass?

No, Abstract is meant to be overridden in subclass so it wont have method body and final means it cannot be overridden in subclass and method body needs to be provided. No. This is so because an abstract method is there for implementation. Putting a final is illegal.

Is it possible to extend an abstract class in Java?

Take a look at the Template method pattern for an example. Classes that extend Game would still need to implement all abstract methods, but they’d be unable to extend playOneGame because it is declared final. An abstract class can also have methods that are neither abstract nor final, just regular methods.