Thread Problem

[Krishna Pratap Singh]

I have been trying to solve a problem involving thread communication using wait() and notify(). Basically i have 2 threads T1 and T2 and i want them to be executed in the following order

T1 , T2, T1, T2 ..... How can i achieve that?

Actual Problem: There are 2 threads T1 - which prints odd numbers (say 1 - 100) and T2 - which prints even numbers (1 - 100). Now, the output should be 1, 2, 3, 4 , 5 , .... 100

[Harsha Smith]

Here is the code

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;


public class TwoThreads {

	OddNumbers oddNumbers = new OddNumbers(this);
	EvenNumbers evenNumbers = new EvenNumbers(this);
	int i=1;
	ExecutorService exec = Executors.newCachedThreadPool();
	
	public static void main(String[] args) {
		
		new TwoThreads();
	}
	
	public TwoThreads(){
		exec.execute(oddNumbers);
		exec.execute(evenNumbers);
	}

}

class OddNumbers implements Runnable{
	private TwoThreads twoThreads;
	public OddNumbers(TwoThreads twoThreads) {
		this.twoThreads = twoThreads;
	}

	@Override
	public void run() {
	  try{
		  
		  synchronized(this){
		while(twoThreads.i<=100){
			
			if(twoThreads.i%2==0){
				wait();
			}
			System.out.println(twoThreads.i);
			
			synchronized(twoThreads.evenNumbers){
				twoThreads.i++;
			twoThreads.evenNumbers.notify();
			TimeUnit.SECONDS.sleep(1);
		}}
	}}
	catch(InterruptedException ie){
		
	}
	}
	
	
}

class EvenNumbers implements Runnable{

	private TwoThreads twoThreads;

	public EvenNumbers(TwoThreads twoThreads) {
		
		this.twoThreads = twoThreads;
	}

	@Override
	public void run() {
		try{
			synchronized(this){
		while(twoThreads.i<=100){
			if(twoThreads.i%2!=0){
			 wait();
				
			}
			System.out.println(twoThreads.i);
			synchronized(twoThreads.oddNumbers){
				twoThreads.i++;
			twoThreads.oddNumbers.notify();
			TimeUnit.SECONDS.sleep(1);
		}}}}
		catch(InterruptedException ie){
			
		}
		
	}
	
}

[Mohamed Sanaulla]

Harsha Smith wrote:Here is the code <code>

Please dont provide the complete code/solution.

You can help by providing hints on how to proceed with the solution.

[Krishna Pratap Singh]

Thank you very much Harsha , It is working properly.

[Randall Twede]

harsha must have a lot of time on his hands lol