OOP in Java | PPL

Object Oriented programming in Java:

Object Oriented programming is a programming style which is associated with the concepts like class, object, Inheritance, Encapsulation, Abstraction, Polymorphism.

Class: A class is a collection of method and variables.

We can define a class using the class keyword and the class body enclosed by a pair of curly braces, as shown in the following example:

public class A
{

}

Inheritance: Inheritance feature allows code reusability when a class includes property of another class. In Java “extends” is used to represent inheritance, as shown in the following example:

public class Papa {
 
}

class Child extends Papa {

}

Objects: Object is a component of a program that knows how to perform certain actions and how to interact with other elements of the program, as shown in the following example:

Rectangle Rect = new Rectangle();

Here, Rectangle is a class, Rect is an object of class Rectangle, new is a keyword, Rectangle() is a constructor of class Rectangle.

Abstraction: Abstraction can be achieved using abstract classes in Java. Abstract classes contain abstract methods, which are implemented by the derived class.

Encapsulation: Encapsulation means bundling of data and methods within one unit, e.g., a class in Java. Encapsulation enables a programmer to implement the desired level of abstraction.

Polymorphism: Polymorphism means overloading and overriding, as shown in the following example:

Polymorphism overloading example:

 public class OverLoading
 {
   public void sum(int a, int b)
   {
     System.out.println(a + b);
   }
   public void sum(int a, int b, int c)
   {
     System.out.println(a + b + c );
   }

}

Polymorphism overriding example:

 public class Parent
 {
   public virtual void Show()
   {
     System.out.println("Welcome");
   }
 }
 
 public class Child extends Parent
 {
   public override void Show()
   {
     System.out.println("Swagatam");
   }
 }

Principles of Programming Languages:

EasyExamNotes.com covered following topics in PPL.

• Language Evaluation Criteria
• Influences on Language Design 
• Language Categories
• Programming Paradigms
• Compilation
• Virtual Machines 
• Programming Environments
• Issues in Language Translation
• Parse Tree 
• Pointer and Reference type
• Concept of Binding
• Type Checking
• Strong typing 
• Sequence control with Expression
• Exception Handling 
• Subprograms
• Fundamentals of sub-programs
• Scope and lifetime of variable
• Static and dynamic scope
• Design issues of subprogram and operations
• Local referencing environments
• Parameter passing methods
• Overloaded sub-programs
• Generic sub-programs 
• Design issues for functions 
• Co routines 
• Abstract Data types
• Abstraction and encapsulation
• Static and Stack-Based Storage management
• Garbage Collection
• OOP in C++
• OOP in Java 
• OOP in C# 
• OOP in PHP
• Concurrency
• Semaphores 
• Monitors
• Message passing
• Java threads 
• C# threads 
• Exception handling 
• Exceptions
• Exception Propagation 
• Exception handler in C++ 
• Exception handler in Java
• Introduction and overview of Logic programming
• Basic elements of Prolog
• Application of Logic programming
• Functional programming languages
• Introduction to 4GL 

Practicals:

• Memory Implementation of 2D Array. 
• Memory Implementation of 3D Array. 
• Implementation of pointers in C++. 
• Write a program in Java to implement exception handling.
• Write a program in C++ to implement call by value parameter passing Method.
• Write a program in C++ to implement call by reference parameter passing Method. 
• Write a program in Java to implement concurrent execution of a job using threads.
• Implement Inheritance in C#.
• Implement Encapsulation in C#.
• Implement static/compiletime Polymorphism in C#.
• Implement dynamic/runtime Polymorphism in C#.

Previous years solved papers:

• PPL|RGPV|May 2018 
• PPL|RGPV|June 2017 

A list of Video lectures

• Click here

References:

1. Sebesta,”Concept of programming Language”, Pearson Edu 
2. Louden, “Programming Languages: Principles & Practices” , Cengage Learning 
3. Tucker, “Programming Languages: Principles and paradigms “, Tata McGraw –Hill. 
4. E Horowitz, "Programming Languages", 2nd Edition, Addison Wesley