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Java Exception Handling MCQ Test

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Creating Threads

 In Java, there are two primary ways to create threads:

1. Extending the `Thread` class: You can create a new class that extends the `Thread` class and override its `run()` method to define the code that the thread will execute.


2. Implementing the `Runnable` interface: You can create a class that implements the `Runnable` interface and provide the implementation for its `run()` method. Then, you can pass an instance of this class to a `Thread` object.


Let's see examples for both approaches:

 1. Extending the `Thread` class:


class MyThread extends Thread {

    public void run() {

        // Code to be executed by the thread

        for (int i = 0; i < 5; i++) {

            System.out.println("Thread: " + i);

            try {

                Thread.sleep(1000); // Pause execution for 1 second

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

    }

}


public class Main {

    public static void main(String[] args) {

        MyThread thread = new MyThread();

        thread.start(); // Start the thread

    }

}


2. Implementing the `Runnable` interface:


class MyRunnable implements Runnable {

    public void run() {

        // Code to be executed by the thread

        for (int i = 0; i < 5; i++) {

            System.out.println("Runnable: " + i);

            try {

                Thread.sleep(1000); // Pause execution for 1 second

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

    }

}


public class Main {

    public static void main(String[] args) {

        MyRunnable myRunnable = new MyRunnable();

        Thread thread = new Thread(myRunnable);

        thread.start(); // Start the thread

    }

}



Both approaches will create a separate thread of execution, allowing the code within the `run()` method (defined in either the `Thread` subclass or the `Runnable` implementation) to run concurrently with the main program.


Remember to call the `start()` method on the `Thread` object to start the execution of the thread. Do not call the `run()` method directly, as it will execute in the same thread as the caller, not in a separate thread.

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