Object Oriented Programming Questions Long
The 'final' keyword in Object Oriented Programming serves multiple purposes.
Firstly, when applied to a class, the 'final' keyword indicates that the class cannot be subclassed or extended. This means that no other class can inherit from the final class, preventing any modifications or extensions to its behavior. This is useful when a class is designed to be immutable or when its functionality should not be altered.
Secondly, when applied to a method, the 'final' keyword indicates that the method cannot be overridden by any subclass. This ensures that the behavior of the method remains consistent across all subclasses, preventing any modifications to its implementation. This is particularly useful when a method is critical to the functionality of a class and should not be altered.
Thirdly, when applied to a variable, the 'final' keyword indicates that the variable's value cannot be changed once it has been assigned. This creates a constant variable that remains unchanged throughout the program's execution. This is beneficial when a variable's value should not be modified, such as a mathematical constant or a configuration parameter.
Additionally, the 'final' keyword can also be used to define a finalizer method in a class. A finalizer method is called by the garbage collector before an object is destroyed, allowing the object to perform any necessary cleanup operations. By using the 'final' keyword, the finalizer method cannot be overridden or modified by any subclass.
Overall, the 'final' keyword in Object Oriented Programming provides a way to enforce immutability, prevent inheritance or method overriding, create constant variables, and define finalizer methods. It helps in ensuring the integrity and consistency of classes, methods, and variables within an object-oriented system.