Java 1.Conclude the usage of the keyword final and static. 2.Introduction of Parent Delegation Model

1. The keyword final is used to declare a constant variable, which means the value of the variable cannot be changed once it is assigned. It can also be used to make a method or class immutable, which means they cannot be overridden or extended by any subclass.

The keyword static is used to define a class-level or static variable, method, or block. A static variable belongs to the class and is shared by all instances of the class. A static method can be called without creating an instance of the class. A static block is used to initialize static variables when the class is loaded.

2. The Parent Delegation Model is a design pattern used in object-oriented programming, where a subclass delegates some or all of its functionality to its parent class. In this model, the parent class is responsible for providing the common functionality to all its subclasses, while the subclasses only add or modify their own specific functionality.

This model is used in many programming languages, including Java, where it is implemented through the concept of inheritance. In Java, a subclass can inherit the properties and methods of its parent class using the extends keyword. The subclass can then use these inherited properties and methods, as well as add its own properties and methods.

The Parent Delegation Model is a powerful technique that promotes code reuse and reduces duplication of code. It also makes it easier to maintain and update code, as changes made to the parent class are automatically inherited by all its subclasses.