How Does Default Virtual Behavior Differ in C++ and Java?

Let us discuss how the default virtual behavior of methods is opposite in C++ and Java. It is very important to remember that in the C++ language class member methods are non-virtual by default. They can be made virtual by using virtual keywords. For example, Base::show() is non-virtual in following program and program prints "Base::show() called". 

Example:

Output: 

Base::show() called

Output Explanation: Adding virtual before definition of Base::show() makes program print "Derived::show() called". In Java, methods are virtual by default and can be made non-virtual by using the final keyword. For example, in the following java program, show() is by default virtual and the program prints "Derived::show() called".

Let us see what happens in the case we use the same concept in a java programming language via the example proposed below.

Example:

Derived::show() called

Note: Unlike C++ non-virtual behavior, if we add final before the definition of the show() in Base, then the above program fails in the compilation.