Interfaces-in-Java.for engineering students pptx
- 1. Interfaces in Java Java Interfaces are blueprints for classes. They define a contract that classes can implement. This helps to create modular and reusable code. by Gulshan Kumar
- 2. What are Interfaces? 1 Contracts Interfaces define a set of methods that a class must implement. They provide a structure for interaction. 2 Abstract Behavior Interfaces define what a class should do but not how it should do it. Implementation details are left to the concrete class. 3 Polymorphism Interfaces allow for polymorphism. Different classes can implement the same interface, but they can have their own unique implementations.
- 3. Purpose and Benefits of Interfaces Abstraction Interfaces hide implementation details, focusing on behavior. This simplifies code and promotes modularity. Flexibility Interfaces allow for dynamic behavior. You can swap out different implementations of the same interface at runtime. Loose Coupling Classes communicate through interfaces, reducing dependencies and increasing maintainability.
- 4. Interface Syntax and Declaration Keyword Interfaces are declared using the keyword "interface". Methods Interfaces define methods without implementation. They only contain method signatures. Example interface Drawable { void draw(); }
- 5. Implementing Interfaces Interface An interface defines a contract for a class. Implementation A class implements the interface by providing concrete implementations for the interface methods. Object The class can now be used as an object of the interface type.
- 6. Default and Static Methods in Interfaces Default Methods with implementations provided in the interface. Static Methods associated with the interface itself, not individual implementations.
- 7. Interface Inheritance 1 Subinterfaces Interfaces can inherit from other interfaces using the "extends" keyword. 2 Method Inheritance Subinterfaces inherit all methods (including default methods) from parent interfaces. 3 Multiple Inheritance Interfaces can extend multiple parent interfaces, providing a mechanism for multiple inheritance.
- 8. Functional Interfaces and Lambda Expressions Single Abstract Method A functional interface has only one abstract method. Lambda Expressions Lambda expressions provide a concise way to implement functional interfaces. Example Interface with a single abstract method "apply" and an example lambda expression.
- 9. Java 8 Additions to Interfaces 1 Default Methods Allow interfaces to provide default implementations for methods. 2 Static Methods Allow interfaces to have static methods, useful for utility functions. 3 Lambda Expressions Enable concise and functional programming style, working with functional interfaces.
- 10. Advantages and Disadvantages of Interfaces Advantages • Abstraction • Flexibility • Loose Coupling • Polymorphism Disadvantages • Complexity • Overhead • Overuse Can Lead to Fragile Code