Introduction to Java

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Java is a class-based, object-oriented programming language built to be platform-independent. Its motto is “Write Once, Run Anywhere”: compiled Java runs on any platform that supports Java, no recompiling needed.

What is Java?

Java is a high-level, class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible. It is a general-purpose programming language intended to let programmers write once, run anywhere (WORA).

Key Features of Java

  • Platform Independent: Java code can run on any platform that has a Java Virtual Machine (JVM)
  • Object-Oriented: Everything in Java is an object, which helps in organizing code
  • Secure: Java’s security features help protect against viruses and malicious code
  • Robust: Strong type checking and exception handling make Java programs reliable
  • Multithreaded: Java supports multithreading, allowing concurrent execution of two or more threads

Getting Started with Java

To start programming in Java, you need to:

  1. Install the Java Development Kit (JDK)
  2. Set up your environment variables
  3. Write your first Java program

Here’s a simple “Hello, World!” program in Java:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

Java Development Tools

  • JDK (Java Development Kit): Contains tools for developing Java applications
  • JRE (Java Runtime Environment): Contains the JVM and libraries needed to run Java applications
  • IDEs: Popular IDEs for Java development include IntelliJ IDEA, Eclipse, and VS Code

Next Steps

In the next sections, we’ll cover:

  • Variables and Data Types
  • Control Structures
  • Classes and Objects
  • Inheritance and Polymorphism
  • Exception Handling
  • Collections Framework
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