Download to read offline
OOP Programming TEchniques used in Java
- 1.
- 2. ▪ Object-Oriented Programming(OOP) in Java is a programming paradigm centered around the concept of objects, which are instances of classes. ▪ OOP is built around four key principles. ▪ Inheritance ▪ Abstract ▪ Encapsulation ▪ Polymorphism OOP in Java
- 3.
- 4. ▪ Inheritance isone of the useful feature of OOPs. It allows a class to inherit the properties and methods of another class. ▪ A class inheriting properties and methods of another class can use those without declaring them. ▪ The main purpose of inheritance in java is to provide the reusability of code. ▪ So that a class has to write only the unique features and rest of the common properties and functionalities can be inherited from another class. Inheritance
- 5.
- 6. ▪ A classcan only inherit the fields (or properties) and methods of another class, if it extends the class. ▪ Child Class: ▪ The class that extends the features of another class is known as child class, sub class or derived class. In the above code, class A is the child class. ▪ Parent Class: ▪ The class that shares the fields and methods with the child class is known as parent class, super class or Base class. In the above code, Class B is the parent class. Inheritance
- 7. ▪ Inheritance removesredundancy from the code. A class can reuse the fields and methods of parent class. No need to rewrite the same redundant code again. ▪ Inheritance allows us to reuse of code, it improves reusability in your java application. ▪ Reduces code size: By removing redundant code, it reduces the number of lines of the code. ▪ Improves logical structure: Improves the logical structure of the code that allows programmer to visualize the relationship between different classes. Advantages of using Inheritance
- 8. Types of Inheritance •There are four types of inheritance in Java: • Single • Multilevel • Hierarchical • Hybrid
- 9.
- 10.
- 11.
- 12.
- 13.
- 14.
- 15. ▪ Polymorphism inJava is one of the four fundamental principles of Object-Oriented Programming (OOP). ▪ The term "polymorphism" means "many forms," and in Java, it allows objects to take on multiple forms. ▪ Polymorphism enables a single interface to be used to represent different underlying forms (data types or methods). Polymorphism
- 16.
- 17. ▪ Types ofpolymorphism. Polymorphism
- 18. ▪ Types ofpolymorphism. Polymorphism
- 19. ▪ Reusability: Writecode that works with multiple types. ▪ Flexibility and Scalability: Handle new types with minimal changes to existing code. ▪ Reduced Coupling: Allows loosely coupled design. ▪ Improved Maintainability: Makes code easier to manage and extend. Advantages of Polymorphism
- 20.
- 21. ▪ It isthe process of grouping the data with its related methods into single unit(Class). ▪ To prevent unauthorized access to data members of object. ▪ In Java, encapsulation is primarily implemented by: ▪ Declaring fields (variables) as private. ▪ Providing public getter and setter methods to access and modify the fields. Encapsulation
- 22. ▪ Data Hiding:Prevents unauthorized access to sensitive data. ▪ Improved Security: Restricts unwanted changes to the fields. ▪ Flexibility: Allows changes in the implementation without affecting external code. ▪ Code Reusability: Promotes modular and maintainable code. Encapsulation
- 23.
- 24. Abstraction • Abstraction inJava is one of the four pillars of Object-Oriented Programming (OOP). • It focuses on hiding the implementation details of a class and showing only the essential features (or behavior) to the user. • This helps to reduce complexity and increase the readability of the code. • Key concepts of abstraction: • Hiding Implementation: The user interacts with the high-level operations, without knowing the underlying complexities.
- 25. Abstraction • Show OnlyWhat is Necessary: Expose only the methods that are needed and hide the rest. • Achieved By: • Abstract Classes • Interfaces
- 26. Abstract Classes • Anabstract class is a class that is declared using the abstract keyword. • It can contain abstract methods (methods without a body) and concrete methods (methods with a body). • Characteristics of Abstract Classes: • Cannot be instantiated (you cannot create an object of an abstract class). • Can have both abstract and non-abstract methods. • Can have constructors, fields, and static methods.
- 27.
- 28. Interfaces • An interfaceis a blueprint of a class that contains abstract methods. • In Java 8 and later, it can also contain default and static methods. • Characteristics of Interfaces: • All methods in an interface are implicitly abstract and public (prior to Java 8). • Cannot contain constructors or instance fields (only constants). • A class can implement multiple interfaces, supporting multiple inheritance.
- 29.
- 30. Constructors • A constructorin Java is a special method used to initialize objects. • It is called when an object of a class is created. • A constructor has the same name as the class and does not have a return type, not even void. • Key Features of a Constructor • Name: Must be the same as the class name. • No Return Type: Does not have any return type. • Automatic Invocation: Called automatically when an object is created. • Can Be Overloaded: Multiple constructors can be defined in a class with different parameter lists.
- 31. Constructors • Types ofConstructors in Java 1. Default Constructor: • No arguments. • Automatically provided by Java if no constructors are explicitly defined. 2. Parameterized Constructor: • Takes arguments to initialize the object with specific values.
- 32. Add a SlideTitle - 5