abstract class vs final class

Abstract class and Final class are very different basically in their nature and usage in Java language. Both are very contrary in their functionality.

Following table gives the differences: abstract class vs final class.

Property	Abstract class	Final class
Subclassing	Should be subclassed to override the functionality of abstract methods	Can never be subclassed as final does not permit
Method alterations	Abstract class methods functionality can be altered in subclass	Final class methods should be used as it is by other classes
Instantiation	Cannot be instantiated	Can be instantiated
Overriding concept	For later use, all the abstract methods should be overridden	Overriding concept does not arise as final class cannot be inherited
Inheritance	Can be inherited	Cannot be inherited
Abstract methods	Can contain abstract methods	Cannot contain abstract methods
Partial implementation	A few methods can be implemented and a few cannot	All methods should have implementation
Immutable objects	Cannot create immutable objects (infact, no objects can be created)	Immutable objects can be created (eg. String class)
Nature	It is an incomplete class (for this reason only, designers do not allow to create objects)	It is a complete class (in the sense, all methods have complete functionality or meaning)
Adding extra functionality	Extra functionality to the methods can be added in subclass	No extra functionality can be added and should be used as it is

I am sure now you are clear of abstract class vs final class.

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