Parallel task sink with kill signaling in Java

import org.zeromq.ZMQ;

/**
* Task sink - design 2
* Adds pub-sub flow to send kill signal to workers
*/

public class tasksink2 {

public static void main (String[] args) throws Exception {

// Prepare our context and socket
ZMQ.Context context = ZMQ.context(1);
ZMQ.Socket receiver = context.socket(ZMQ.PULL);
receiver.bind("tcp://*:5558");

// Socket for worker control
ZMQ.Socket controller = context.socket(ZMQ.PUB);
controller.bind("tcp://*:5559");

// Wait for start of batch
receiver.recv(0);

// Start our clock now
long tstart = System.currentTimeMillis();

// Process 100 confirmations
int task_nbr;
for (task_nbr = 0; task_nbr < 100; task_nbr++) {
receiver.recv(0);
if ((task_nbr / 10) * 10 == task_nbr) {
System.out.print(":");
} else {
System.out.print(".");
}
System.out.flush();
}
// Calculate and report duration of batch
long tend = System.currentTimeMillis();

System.out.println("Total elapsed time: " + (tend - tstart) + " msec");

// Send the kill signal to the workers
controller.send("KILL", 0);

// Give it some time to deliver
Thread.sleep(1);

receiver.close();
controller.close();
context.term();
}
}