Java (OpenJDK) Online Compiler & Code Runner

Run Java programs in your browser with zero setup. Write classes, test algorithms with `java.util.*`, and execute standard Java code directly.

Full Java Collections Framework

Use ArrayList, HashMap, HashSet, PriorityQueue, and Streams.

Standard Input Ready

Pass custom input through `Scanner` or `BufferedReader` seamlessly.

Popular Java (OpenJDK) Examples

Scanner User Input

Reading integers and strings using java.util.Scanner.

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter your name: ");
        if (sc.hasNext()) {
            System.out.println("Welcome, " + sc.next() + "!");
        }
    }
}

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Frequently Asked Questions

What should be the main class name?

Name your public class `Main` with the standard `public static void main(String[] args)` signature.