THE FINAL KEYWORD CAN BE USED BEFORE A CLASS, METHOD, VARIABLE
Final Classes When used in a class declaration, -the final keyword before class means the class can't be subclassed. In other words, no other class can ever extend (inherit from) a final class, and any attempts to do so will give you a compiler error.
For example, the String class cannot be subclassed because it is final
Final method- the final keyword before a method means we can not override the method.
Final variable- the final keyword before a variable means it becomes a constant and the value can not be changed further.