Explain how to utilise wrapper classes for non-object data types to avoid mixing non-object and object values.

Polymorphism: Why is it needed especially from an OOP standpoint? What is the essential concept when you cast objects regarding Polymorphism/Inheritance? (Related Chapters 11,12,13, 19) Generics: Explain Generic Programming. Why is generics important as a data type regarding objects? Polymorphism and Objects: Explain an array of polymorphic objects in a single/double dimensional array. How do you access this? How do you process this? When would you use this?    Also, when the new topic/chapter is posted regarding File/IO: Write a few lines of code that allow you to save/retrieve this data from a file using the appropriate class/methods. Do this in two ways: StreamFile I/O and URL access. You can also illustrate this in your code via text (.txt) and binary (.dat) data access.  Also, write a few more additional lines of code illustrating StreamFile  I/O access for .txt and .bin files.

Calculator Assignment Modify a calculator program that currently displays the Abstract Syntax Tree (AST) structure after parsing an input expression. Instead of printing the AST, enhance the program to evaluate the expression and display the result. Add support for the binary "%" remainder (modulo) operator and introduce variables with the assignment operator "=". Key steps to implement the assignment operator and variables: Introduce a new static attribute in the AstNode class to represent variables: Add a method isIdentifier() to the TokenStream class to detect variables: Modify the primaryRule() in AstNode to handle variables and variable assignment: Handle new node types in the AstNode evaluate() method for variables and assignment: These changes allow the calculator to evaluate expressions, support variables, and handle variable assignments. Users can create and use variables in subsequent expressions.EmployeeJava Type:  package week3;import static week3.MainApp.*; public enum…