creating user defined threads

[Mohan Mehra]

I know how to create threads but I need to create threads based on user input, i.e., if you mention 5 then 5 threads have to be generated. each thread has different tasks to do.

[Jeff Verdegan]

Mohan Mehra wrote:I know how to create threads but I need to create threads based on user input, i.e., if you mention 5 then 5 threads have to be generated.

So use a loop.

each thread has different tasks to do.

Then you must have some logic for deciding which task to assign to each thread. Nobody here can tell you how to do that, since it depends on your requirements, which you haven't specified.

[Mohan Mehra]

each thread generated will independently generate a random integer as an upper limit, and then computes and prints the no. of primes less than or equal to that upper limit .

simple program to create thread:

public class MyThread extends Thread {
    
    /**
     * This method is executed when the start() method is called on the thread
     * so here you will put the 'thread code'.
     */
    public void run() {
        System.out.println("Thread executed!");
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Thread thread = new MyThread();
        thread.start();
    }
}

[Henry Wong]

Simply... replace this code ...

Mohan Mehra wrote:

    /**
     * This method is executed when the start() method is called on the thread
     * so here you will put the 'thread code'.
     */
    public void run() {
        System.out.println("Thread executed!");
    }

with something that does this...

Mohan Mehra wrote:independently generate a random integer as an upper limit, and then computes and prints the no. of primes less than or equal to that upper limit .

Also, modify this code ...

Mohan Mehra wrote:

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Thread thread = new MyThread();
        thread.start();
    }
}

to start many threads by adding ...

Jeff Verdegan wrote:
So use a loop.

whose range is controlled or obtained ...

Mohan Mehra wrote:if you mention 5 then 5 threads have to be generated.

from some input source.


Also ... Since most, if not all of this problem is not thread related, it may be best to implement and test the components without threads first. So, do you have code that generates a random number? that gets input from a user? that generate prime numbers?

Henry

[Rakesh K. Cherukuri]

@Henry Wong : Nicely put...

@Mohan Mehra : as Henry rightly put, address it step by step basis. Not to be rude but a word of advice: These forums are here to help you understand things and code better. That means a fair amount of home work by original poster is expected. Bottom line - please do not expect people to code it for you.

[Mohan Mehra]

done it. here the code

import java.util.Random;
import java.util.Scanner;

public class MyThread extends Thread {  
      
    /** 
     * This method is executed when the start() method is called on the thread 
     * so here you will put the 'thread code'. 
     */  
	public void run() {
		int p;
		int count = 0;
		Random rand = new Random();
		int num = rand.nextInt(100);
		System.out.println("Generated Random Number between 0 to 100 is : "
				+ num);
		/*
		 * int numNoRange = rand.nextInt();System.out.println(
		 * "Generated Random Number without specifying any range is : " +
		 * numNoRange);
		 */
		System.out.println("Thread executed!");
		for (int i = 2; i <= num; i++) {
			p = 0;
			for (int j = 2; j < i; j++) {
				if (i % j == 0)
					p = 1;
			}
			if (p == 0) {
				count++;
				System.out.println(i);

			}
		}
		System.out.println("count: " + count);
	}
      
    /** 
     * @param args the command line arguments 
     */  
    public static void main(String[] args) { 
    	int n;
    	Scanner s=new Scanner(System.in);
    	System.out.println("Enter the no. of threads to generate:");
    	n=s.nextInt();
    	for(int i=0;i<n;i++){
        Thread thread = new MyThread();  
        thread.start();  
    	}
    }  
}