Java Online Compiler

// Simple Java Program
public class Main {
    public static void main(String[] args) {
        System.out.println("Java Online Compiler");
    }
}

// ===============================
// 1. HELLO WORLD PROGRAM
// ===============================
public class Main {

  public static void main(String[] args) {

    System.out.println("Hello Java");
  }
}


// ===============================
// 2. USER INPUT PROGRAM
// ===============================
import java.util.Scanner;

class UserInput {

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);

    System.out.print("Enter your name: ");

    String name = sc.nextLine();

    System.out.println("Welcome " + name);

    sc.close();
  }
}


// ===============================
// 3. LOOP EXAMPLE
// ===============================
class LoopExample {

  public static void main(String[] args) {

    for (int i = 1; i <= 5; i++) {
      System.out.println(i);
    }
  }
}


// ===============================
// 4. ARRAY PROGRAM
// ===============================
class ArrayProgram {

  public static void main(String[] args) {

    int[] arr = {1, 2, 3};

    for (int num : arr) {
      System.out.println(num);
    }
  }
}


// ===============================
// 5. OOP PROGRAM
// ===============================
class Student {

  int id;
  String name;

  Student(int id, String name) {
    this.id = id;
    this.name = name;
  }

  void display() {
    System.out.println(id + " " + name);
  }

  public static void main(String[] args) {

    Student s = new Student(1, "Java");

    s.display();
  }
}


// ===============================
// 6. EXCEPTION HANDLING
// ===============================
class ExceptionDemo {

  public static void main(String[] args) {

    try {

      int result = 10 / 0;

      System.out.println(result);

    } catch (Exception e) {

      System.out.println("Exception handled");
    }
  }
}

• 1 Browser-based Java execution tool
• 2 Compile and run Java code online
• 3 No installation required
• 4 Useful for beginners and students

• 1 Code editor
• 2 Compile and execute programs
• 3 Error display
• 4 Quick code testing

• 1 Easy learning environment
• 2 Quick coding practice
• 3 Accessible from anywhere
• 4 Good for interview preparation

• 1 Loops and conditions
• 2 Arrays and strings
• 3 OOP concepts
• 4 Collections and exceptions

• 1 Practice daily
• 2 Understand errors carefully
• 3 Write clean code
• 4 Test multiple scenarios