Multithreading in Java: A Beginner’s Guide to Handling Concurrency

#javabackend #multithreading #concurrency #threadsynchronization

When I first started learning Java backend development, I hit a challenge: handling multiple user requests at the same time. For example, when two users tried to update shared data, my program sometimes returned inconsistent results. That’s when I realized I needed to understand multithreading and concurrency in Java.

What Is Multithreading?

Multithreading means running multiple tasks (threads) simultaneously inside a program. In backend systems, this is crucial for:

Handling concurrent user requests.

Improving performance.

Preventing applications from “freezing” when one task is slow.

Key Concepts in Multithreading

Thread: A lightweight unit of execution. You can create a thread by extending Thread or implementing Runnable.

Runnable: A functional interface used to define the task a thread will execute.

Synchronization: A way to control access to shared resources so multiple threads don’t cause inconsistent data.

Thread Safety: Writing code that behaves correctly even when accessed by multiple threads simultaneously.

Quick Example: Creating a Thread

class MyTask implements Runnable {
    public void run() {
        System.out.println("Task is running in: " + Thread.currentThread().getName());
    }
}

public class Main {
    public static void main(String[] args) {
        Thread thread = new Thread(new MyTask());
        thread.start();
    }
}