Java Tutorial
Last Updated: April 30, 2025
Welcome to our comprehensive Core Java programming tutorial, specially crafted for students and working professionals. Java is a robust, class-based, object-oriented, concurrent, and secure programming language widely used across industries for building powerful applications.
What is Java?
Java is both a programming language and a computing platform. It is a high-level, secure, object-oriented language known for its portability, performance, and ease of use.
Java was originally developed by Sun Microsystems (now a part of Oracle Corporation) in 1995. It was created by James Gosling, who is regarded as the father of Java. Initially, the language was called Oak, but the name was later changed to Java due to trademark issues.
Why Java is Called a Platform
A platform is any hardware or software environment where a program runs. Java is considered a platform because it comes with its own runtime environment (JRE) and a rich set of libraries (API), which together enable Java applications to run independently of the underlying hardware.
Java Example: Hello World
Here’s a simple Java program to get you started:
A step-by-step explanation of this example will be provided in the next section.
Getting Started with Java
Before you start coding in Java, you need to set up your development environment.
Download the JDK
Install the Java Development Kit (JDK) from the official Oracle website. The JDK includes essential tools such as the Java compiler.Choose an Editor or IDE
You can write Java code using a simple text editor or opt for an Integrated Development Environment (IDE) like:IntelliJ IDEA
Eclipse
NetBeans
IDEs provide features like code suggestions, debugging tools, and project management that streamline the development process.
Where is Java Used?
Java powers billions of devices worldwide and is used in a wide range of applications, including:
Desktop Applications – e.g., Media players, antivirus software, PDF readers
Web Applications – e.g., booking systems, content management systems
Enterprise Applications – especially in banking and finance
Mobile Applications
Embedded Systems
Smart Cards
Robotics
Game Development