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Ravi Vishwakarma

Ravi Vishwakarma

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Ravi Vishwakarma is a dedicated Software Developer with a passion for crafting efficient and innovative solutions. With a keen eye for detail and years of experience, he excels in developing robust software systems that meet client needs. His expertise spans across multiple programming languages and technologies, making him a valuable asset in any software development project.

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Ravi Vishwakarma

Ravi Vishwakarma

24-Apr-2025

1. Extending Thread class

Example:

class MyThread extends Thread {
    public void run() {
        System.out.println("Thread running: " + Thread.currentThread().getName());
    }

    public static void main(String[] args) {
        MyThread t1 = new MyThread();
        t1.start(); // starts the thread
    }
}

Notes:

  1. run() contains the code to be executed in the new thread.
  2. start() creates a new thread and then calls run() internally.

2. Implementing Runnable interface

Example:

class MyRunnable implements Runnable {
    public void run() {
        System.out.println("Runnable thread: " + Thread.currentThread().getName());
    }

    public static void main(String[] args) {
        MyRunnable runnable = new MyRunnable();
        Thread t1 = new Thread(runnable); // pass the runnable to a Thread
        t1.start();
    }
}

Why use Runnable?

  1. More flexible (you can extend another class).
  2. Preferred when you want to share the same task between threads.

3. Using Lambda (Java 8+)

If your logic is simple, you can use a lambda expression instead of writing a separate class.

Example:

public class LambdaThreadExample {
    public static void main(String[] args) {
        Thread t = new Thread(() -> {
            System.out.println("Lambda thread: " + Thread.currentThread().getName());
        });
        t.start();
    }
}

Summary:

Method Use When
extends Thread You don't need to extend another class
implements Runnable You want to extend another class or share logic
Lambda with Runnable For short, clean, and inline thread code

Bonus: Sleep, Join, and Priority

Thread.sleep(1000); // pause for 1 sec
t1.join();          // wait for t1 to finish
t1.setPriority(8);  // set priority (1 to 10)

 

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