First Java Program - Hello World Example

Your First Java Program

Let's write the traditional "Hello, World!" program.

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

class HelloWorld: Defines a class named HelloWorld. In Java, every line of code must run inside a class.

public static void main: The entry point. The JVM looks for this method to start execution.

System.out.println: Prints text to the console.

Save file as HelloWorld.java.

Open terminal/command prompt.

Compile: javac HelloWorld.java (Creates HelloWorld.class).

Run: java HelloWorld (Outputs: Hello, World!).

What is the main method?

public static void main(String[] args) is the entry point of any Java application.