Quick Answer: Can We Inherit Final Class?

Can a final class extend other classes?

A final class can extend other classes, It can be a subclass but not a superclass.

Simply, when we need to create an immutable class then the final class is the best answer..

Can a constructor be final?

No, a constructor can’t be made final. A final method cannot be overridden by any subclasses. … In other words, constructors cannot be inherited in Java therefore, there is no need to write final before constructors.

How do I make my class final?

To create an immutable class in Java, you have to do the following steps.Declare the class as final so it can’t be extended.Make all fields private so that direct access is not allowed.Don’t provide setter methods for variables.Make all mutable fields final so that its value can be assigned only once.More items…

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.

What makes a class immutable?

Immutable class means that once an object is created, we cannot change its content. In Java, all the wrapper classes (like Integer, Boolean, Byte, Short) and String class is immutable. … Data members in the class must be declared as final (So that we can’t change the value of it after object creation)

Can a constructor be static?

A static constructor does not take access modifiers or have parameters. A class or struct can only have one static constructor. Static constructors cannot be inherited or overloaded. A static constructor cannot be called directly and is only meant to be called by the common language runtime (CLR).

Why we Cannot override static method?

Static methods cannot be overridden because they are not dispatched on the object instance at runtime. The compiler decides which method gets called. Static methods can be overloaded (meaning that you can have the same method name for several methods as long as they have different parameter types).

Can static method be overloaded?

Can we override a static method? No, we cannot override static methods because method overriding is based on dynamic binding at runtime and the static methods are bonded using static binding at compile time. So, we cannot override static methods.

Which class can not be extended?

The final modifier When used on a class declaration, it means that the class cannot be extended. (i.e. it cannot become a parent class to a new subclass) When used on a method declaration, it means that the method cannot be overridden in a subclass.

Can we inherit a final method in Java?

No, we cannot override a final method in Java. The final modifier for finalizing the implementations of classes, methods, and variables. We can declare a method as final, once you declare a method final it cannot be overridden.

Can we create an object of final class?

Yes, it’s possible to make an object of final class. If you forgot then String is a final class and you have created objects of it many times. Final only restrict the class to be inherited by another class, it won’t let you down in creating an object of it.

Can we declare constructor as private?

Yes, we can declare a constructor as private. If we declare a constructor as private we are not able to create an object of a class. We can use this private constructor in the Singleton Design Pattern.

What happens if a class is declared as final?

When a class is declared with final keyword, it is called a final class. A final class cannot be extended(inherited). … The other use of final with classes is to create an immutable class like the predefined String class. You can not make a class immutable without making it final.

Can final method be overloaded?

private and final methods can be overloaded but they cannot be overridden. It means a class can have more than one private/final methods of same name but a child class cannot override the private/final methods of their base class.

Can main method be overloaded?

Yes, we can overload the main method in Java, but When we execute the class JVM starts execution with public static void main(String[] args) method.

Can overloaded methods be overridden too?

Yes, since the overloaded method is a completely different method in the eyes of the compiler. It depends what you mean. A method can be an override for an overloaded method in a superclass. … However, you cannot have one method that is both a new overload and an override.

When should a class be final?

A final class is a class that can’t be extended. Also methods could be declared as final to indicate that cannot be overridden by subclasses. Preventing the class from being subclassed could be particularly useful if you write APIs or libraries and want to avoid being extended to alter base behaviour.