Category : Java | Sub Category : Java Interview questions | By Prasad Bonam Last updated: 2023-07-12 04:38:09 Viewed : 346
key concepts in Java
Here are some key concepts in Java:
Object-Oriented Programming (OOP): Java is an object-oriented programming language, which means it focuses on creating objects that encapsulate data and behavior. OOP concepts in Java include classes, objects, inheritance, polymorphism, and encapsulation.
Classes and Objects: Classes are templates that define the structure and behavior of objects, while objects are instances of classes that represent real-world entities. Classes define the properties (variables) and behaviors (methods) that objects possess.
Inheritance: Inheritance allows the creation of new classes (derived classes or subclasses) based on existing classes (base classes or superclasses). Subclasses inherit the properties and behaviors of the superclass, and can add new or modify existing features.
Polymorphism: Polymorphism allows objects of different classes to be treated as objects of a common superclass. It allows methods to be overridden in subclasses, enabling different implementations based on the specific object type.
Encapsulation: Encapsulation refers to the bundling of data and methods within a class, hiding the internal details and providing access to the data through methods (getters and setters). It helps in data abstraction and protects data from external interference.
Abstraction: Abstraction involves simplifying complex systems by focusing on the essential features and hiding unnecessary details. In Java, abstraction is achieved through abstract classes and interfaces.
Interfaces: Interfaces define a contract for classes to implement, specifying a set of methods that must be implemented by the implementing classes. They enable the implementation of multiple inheritance and promote loose coupling.
Exception Handling: Exception handling allows the detection and handling of errors or exceptional conditions in Java programs. It involves using try-catch blocks to catch exceptions and handle them gracefully.
Generics: Generics provide a way to create classes, interfaces, and methods that can work with different data types. They allow type safety, code reusability, and help in avoiding type casting.
Multithreading: Java supports multithreading, allowing programs to execute multiple threads concurrently. It helps in achieving parallelism and improves performance. Thread synchronization and coordination are important aspects of multithreaded programming.
These are just a few key concepts in Java. Java also includes features like packages, collections, I/O operations, annotations, and more. It is a versatile and widely-used programming language with a rich set of features and libraries for various application domains.