What will happen when you attempt to compile and run the following code? public class Bground extends Thread{ public static void main(String argv[]){ Bground b = new Bground(); b.run(); } public void start(){ for (int i = 0; i <10; i++){ System.out.println("Value of i = " + i); } } }

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  1. A compile time error indicating that no run method is defined for the Thread class.

  2. A run time error indicating that no run method is defined for the Thread class.

  3. Clean compile and at run time the values 0 to 9 are printed out.

  4. Clean compile but no output at runtime.

Show answer
Correct Option: D

AI Explanation

To answer this question, let's analyze the given code:

public class Bground extends Thread{
    public static void main(String argv[]){
        Bground b = new Bground();
        b.run();
    }

    public void start(){
        for (int i = 0; i &lt; 10; i++){
            System.out.println("Value of i = " + i);
        }
    }
}

In this code, the class Bground extends the Thread class. The Thread class provides a run method that is executed when a thread is started.

However, in this code, the start method is overridden in the Bground class. This start method contains a loop that prints the values of i from 0 to 9.

Now, let's analyze the main method. It creates an instance of the Bground class and calls the run method on it.

The issue with this code is that it directly calls the run method instead of using the start method, which is the correct way to start a thread. When the run method is called directly, it runs in the same thread as the caller. This means that the loop in the start method will execute sequentially without creating a new thread.

Therefore, when you attempt to compile and run this code, it will compile without any errors (hence "Clean compile"), but there will be no output at runtime (hence "no output at runtime"). The correct answer is option D.

If you want the code to create a new thread and execute the loop concurrently, you should change b.run() to b.start(). This will start a new thread that executes the run method, and you will see the values of i printed out.

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