Run Java Programs Online — No JDK Installation Needed
Configuring the Java Development Kit (JDK), setting up JAVA_HOME, and resolving system PATH mismatches on locked-down college lab computers can waste half your practical session. With MyCollegeLab, you get an instant, cloud-isolated OpenJDK 17 runtime on Ubuntu Linux that requires zero installation or administrator privileges.
Our online Java compiler is engineered specifically for university syllabi, covering object-oriented programming (OOP), data structures, algorithms, and semester practical exams. Full interactive stdin support allows programs using Scanner or BufferedReader to accept user inputs seamlessly before executing.
Java Compiler Features
Designed from the ground up to deliver a snappy, reliable development environment tailored for academic coursework and competitive programming:
Modern Java Long-Term Support release with records, pattern matching, sealed classes, and enhanced text blocks alongside classic language syntax.
Supply standard input (System.in) in the dedicated stdin tab before running. Read numbers, strings, and multi-line matrices without terminal hangs.
Classes, single and multilevel inheritance, polymorphism, interfaces, abstract classes, and generics work out-of-the-box.
Capped with -Xmx256m heap memory and a 5-second CPU watchdog to prevent runaway recursion or infinite loops from freezing your browser.
Java Programs to Try
Test these common college laboratory practical programs directly in the editor. Each example demonstrates standard I/O, core algorithmic thinking, or object-oriented design.
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: ");
String name = sc.nextLine();
System.out.println("Hello, " + name + "!");
}
}Aman) before clicking Run.import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int n = sc.nextInt();
int[] arr = new int[n];
for (int i = 0; i < n; i++) arr[i] = sc.nextInt();
for (int i = 0; i < n - 1; i++)
for (int j = 0; j < n - i - 1; j++)
if (arr[j] > arr[j + 1]) {
int t = arr[j]; arr[j] = arr[j+1]; arr[j+1] = t;
}
System.out.print("Sorted: ");
for (int x : arr) System.out.print(x + " ");
}
}5 64 34 25 12 22). Expected output: Sorted: 12 22 25 34 64 .public class Main {
static class Animal {
String name;
Animal(String name) { this.name = name; }
void speak() { System.out.println(name + " makes a sound."); }
}
static class Dog extends Animal {
Dog(String name) { super(name); }
@Override
void speak() { System.out.println(name + " barks!"); }
}
public static void main(String[] args) {
Animal a = new Dog("Buddy");
a.speak();
}
}super(), and runtime polymorphism via method overriding.Java Features Supported in MyCollegeLab
Everything required for undergraduate Computer Science (CS/IT) core Java courses, data structures & algorithms (DSA), and technical interview questions is fully enabled:
try/catch/finally, multi-catch, checked vs unchecked exceptions, and custom exception classes.ArrayList, HashMap, LinkedList, HashSet, and PriorityQueue.Scanner, BufferedReader, InputStreamReader, and formatting.Frequently Asked Questions
Which Java version does MyCollegeLab use?
We run official OpenJDK 17 (LTS) on 64-bit Linux. This guarantees full compatibility with university examination guidelines while supporting contemporary Java enhancements like pattern matching and records.
My class is not named Main. Will it work?
The public class that contains your public static void main(String[] args) entry point must be named Main. This is because the backend compilation script executes javac Main.java && java Main. Additional helper classes can be placed in the same file as non-public classes or nested static classes.
Does Scanner work for reading multiple inputs?
Yes! Enter all your input values into the Standard Input (stdin) tab before pressing Run. Separate multiple numbers or words with spaces or newlines. Each call to sc.nextInt() or sc.nextLine() will consume values in order without blocking.
Can I use java.util collections?
Yes, all standard Java library utilities work right out of the box, including ArrayList, HashMap, LinkedList, PriorityQueue, and Collections.sort(). You only need to add import java.util.*; at the top of your program.