final variables in Java

In Java, we can use final keyword with variables, methods, and classes. When the final keyword is used with a variable of primitive data types such as int, float, etc), the value of the variable cannot be changed. 

Example 1: Usage of final with primitive datatype

Output:

👁 Image

Now you must be wondering what if we do use final keyword non-primitive variables, let us explore the same as we did above with the help of an example. 

Note: Non-primitive variables are always references to objects in Java, the members of the referred object can be changed. final for non-primitive variables just means that they cannot be changed to refer to any other object.

Example 2: Usage of final with primitive datatype 

Successfully executed

Note: A final variable can't be declared inside a function, this is so because scope of local variables of a function are limited to scope of function and declaring it their will be against the principle of immutability. If program demands a constant value then the final variable should be declared at class level and may be used in function.