3 Threads Printing numbers in sequence

Question

I am trying to write a simple code to print numbers in sequence. Scenario is like

Thread  Number
T1        1
T2        2
T3        3
T1        4
T2        5
T3          


        

Answer 1

public class PrintThreadsSequentially {

static int number = 1;
static final int PRINT_NUMBERS_UPTO = 20;
static Object lock = new Object();

static class SequentialThread extends Thread {
    int remainder = 0;
    int noOfThreads = 0;

    public SequentialThread(String name, int remainder, int noOfThreads) {
        super(name);
        this.remainder = remainder;
        this.noOfThreads = noOfThreads;
    }

    @Override
    public void run() {
        while (number < PRINT_NUMBERS_UPTO) {
            synchronized (lock) {
                while (number % noOfThreads != remainder) { // wait for numbers other than remainder
                    try {
                        lock.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                System.out.println(getName() + " value " + number);
                number++;
                lock.notifyAll();
            }
        }
    }
}

public static void main(String[] args) {
    SequentialThread first = new SequentialThread("First Thread", 0, 4);
    SequentialThread second = new SequentialThread("Second Thread", 1, 4);
    SequentialThread third = new SequentialThread("Third Thread", 2, 4);
    SequentialThread fourth = new SequentialThread("Fourth Thread", 3, 4);
    first.start();  second.start();   third.start();  fourth.start();
}

}