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Java Tutorial

Last Updated : 18 Nov, 2024
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Java is a robust, versatile programming language used to build a variety of applications, from mobile apps on Android to large-scale enterprise systems and interactive websites.

Popular platforms like LinkedIn, Amazon, and Netflix rely on Java for their back-end architecture, showcasing its stability and scalability across different environments.

This Java Tutorial is designed for beginners as well as experienced professionals. Whether you're starting your Java journey and looking to understand the basics of Java or its advanced concepts, this free Java tutorial is the perfect resource for you.

First Java Program

Java 
// A Java program to print "Hello World" 
public class GFG { 
    public static void main(String args[]) 
    { 
        System.out.println("Hello World"); 
    } 
}

//Output:"Hello World"

For full explanation of the above Program - Click Here

Table of Content

As you get started with Java, it's crucial to have a solid foundation in place. Concepts like data types, control flow, and functions are essential for any Java developer. To explore these topics more thoroughly, the Java Programming Course offers a great blend of theory and practical exercises to help solidify your understanding before moving on to advanced topics

Overview of Java

Basics of Java

Operators in Java

Flow Control in Java

Input/Output in Java

Arrays in Java

Strings in Java

Methods in Java

OOPS in Java

OOPS in Java refers to Object-Oriented Programming concepts implemented in the Java programming language. Java's OOP features include classes, objects, inheritance, polymorphism, and encapsulation, enabling modular and efficient code development. Understanding OOPS in Java is essential for building robust, scalable, and maintainable software applications.

Classes in Java

Classes in Java are the blueprint for creating objects and defining their properties and behaviors. They are the fundamental building blocks of Java programs, enabling the creation of reusable and modular code. Classes can contain fields, methods, constructors, and nested classes, providing a wide range of functionality and flexibility.

Interfaces in Java

Interfaces in Java are abstract types that define a set of methods that a class must implement. They provide a way to achieve abstraction, multiple inheritance, and loose coupling in Java programs. Interfaces are useful for defining common behaviors and functionalities that can be shared across different classes, leading to more modular and reusable code. Mastering interfaces in Java is crucial for building flexible and extensible software applications.

Collection Framework

Java I/O and Networking

File Handling in Java

Java Regex

Java IO

Java Networking

Java Utilities and New Features

Java SE 8 Features

If you want to know more about Java 8 Features, read this tutorial: Java 8 Features

Java Date & Time

Advanced Java Programming

Java JDBC

If you want to know more about JDBC in Java, read this tutorial: JDBC Tutorial

Packages in Java

Memory Allocation in Java

Exception Handling in Java

Multithreading in Java

If you want to know more about Multithreading in Java, read this tutorial: Multithreading Tutorial

Synchronization in Java

Java Miscellaneous

Interview Questions on Java

Java Projects

Beginner-Level Java Projects

Features of Java

Java is one of the most popular and widely used programming languages.
  • Java has been one of the most popular programming languages for many years.
  • Java is Object Oriented. However, it is not considered as pure object-oriented as it provides support for primitive data types (like int, char, etc)
  • The Java codes are first compiled into byte code (machine-independent code). Then the byte code runs on Java Virtual Machine (JVM) regardless of the underlying architecture.
  • Java syntax is similar to C/C++. But Java does not provide low-level programming functionalities like pointers. Also, Java codes are always written in the form of classes and objects.
  • Java is used in all kinds of applications like Mobile Applications (Android is Java-based), desktop applications, web applications, client-server applications, enterprise applications, and many more.
  • When compared with C++, Java codes are generally more maintainable because Java does not allow many things which may lead to bad/inefficient programming if used incorrectly. For example, non-primitives are always references in Java. So we cannot pass large objects (like we can do in C++) to functions, we always pass references in Java. One more example, since there are no pointers, bad memory access is also not possible.
  • When compared with Python, Java kind of fits between C++ and Python. The programs are written in Java typically run faster than corresponding Python programs and slower than C++. Like C++, Java does static type checking, but Python does not.

Applications of Java

Here in this section, we have added some of the applications that were developed using the Java programming language.

  • Mobile Applications
  • Desktop GUI Applications
  • Artificial intelligence
  • Scientific Applications
  • Cloud Applications
  • Embedded Systems
  • Gaming Applications

Java Practice Problems

Keep up your pace and try hard till you excel in it. This will need some motivation and resources to Practice Java. So, there are few resources mentioned below this will help you in your journey:

Java Jobs & Opportunity

According to report of Statista.com Java is most demanded programming languages after JavaScript by recruiters worldwide in 2024. Major MNC companies are recruiting Java Programmers.

Java Latest & Upcoming Features

Java SE 21
Released: September 2023
Java SE 21 is the latest stable release, featuring:

  • Hidden Classes (Preview): Introduces a mechanism to restrict access to specific members of a class, enhancing modularity and code maintainability.
  • Improved Garbage Collector Ergonomics (JEP 429): Simplifies configuration and monitoring of the garbage collection process.
  • API Updates: Enhancements to existing APIs, including java.io.file for better file handling capabilities.

Java SE 22
Released: March 19, 2024
Java SE 22 introduces:

  • Foreign Function & Memory API (JEP 454): Enhances interoperability with native code.
  • Unnamed Variables & Patterns (JEP 456): Adds support for unnamed variables and patterns.
  • Structured Concurrency (JEP 462, Second Preview): Simplifies multithreaded programming by structuring concurrency.
  • String Templates (JEP 459, Second Preview): Provides a new syntax for creating and manipulating strings.
  • Vector API (JEP 460, Seventh Incubator): Offers a portable and low-level abstraction for SIMD programming.

Upcoming Features (Expected in Java SE 23 - September 2024)

  • Vector API (Incubator): A new API designed for high-performance vector computations, potentially beneficial for scientific computing and machine learning applications.
  • Project Panama (Preview): Aims to improve interoperability between Java and native code, simplifying interactions with non-Java libraries and frameworks.
  • Java continues to prioritize features that enhance application performance and developer experience.
  • Java's strong position in cloud environments is expected to hold as cloud computing remains a dominant trend.
  • Java's suitability for building scalable and modular systems aligns well with the popularity of microservices architectures.
  • Expect to see Java evolving to integrate more seamlessly with technologies like artificial intelligence, big data, and the Internet of Things (IoT).
Java Tutorial

Java Programming Tutorial: FAQs

What is Java?

Developed by Sun Microsystems in 1995, Java is a highly popular, object-oriented programming language. This platform independent programming language is utilized for Android development, web development, artificial intelligence, cloud applications, and much more.

Why use Java ?

Java is simple to understand programming language because doesn’t contain concepts like : Pointers and operator overloading and it is secure and portable.

What are the major concepts in Java?

There are 4 major concept in Java that is abstraction, encapsulation, polymorphism, and inheritance. Along with this Java also works with three OOPs concept

How Java different to C++ ?

C++JAVA
C++ is platform dependent.Java is platform independent.
C++ uses compiler only.Java uses compiler and interpreter both.
C++ support pointers and operator overloading.Java doesn’t support pointers and operator overloading concept.
C++ not support multithreading concept.Java supports multithreading concept.

Java is based on object model hence it is one the popular programming language.

What are the scope of Java Technologies for Web Applications?

Java Technologies for Web Applications are a set of Java-based technologies that are used to develop web applications. These technologies include:

  • Java Servlet API
  • JavaServer Pages
  • JavaServer Faces
  • Enterprise JavaBeans
  • JDBC (Java Database Connectivity)
  • Java Messaging Service (JMS):
  • JavaMail API:
  • JAX-WS

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