import java.lang.Math;

public class JLab0801 {

public static void main(String[] args) {

// TODO Auto-generated method stub

PrintThread thread1,thread2,thread3,thread4;

thread1 = new PrintThread("thread1");

thread2 = new PrintThread("thread2");

thread3 = new PrintThread("thread3");

thread4 = new PrintThread("thread4");

System.err.println("\n Starting threads");

thread1.start();

thread2.start();

thread3.start();

thread4.start();

System.err.println("Threads started\n");

}

}

class PrintThread extends Thread{

private int sleepTime;

public PrintThread(String name){

super(name);

sleepTime = (int)(Math.random() * 5000);

System.err.println("Name:"+getName()+";sleep:"+sleepTime);

}

public void run(){

try{

System.err.println(getName()+" going to sleep");

Thread.sleep(sleepTime);

}catch(InterruptedException interruptedException){

System.err.println(interruptedException.toString());

}

System.err.println(getName()+" done sleeping");

}

}