private void moveHosts(double timeIncrement){
  for (int i=0, n=hosts.size(); i < n; i++) {
    DTNHost host=hosts.get(i);
    host.move(timeIncrement);
  }
}

private void moveHosts ( double timeIncrement ) { for ( int i = 0 , n = hosts . size ( ) ; i < n ; i ++ ) { DTNHost host = hosts . get ( i ) ; host . move ( timeIncrement ) ; } }
moves all hosts in the world for a given amount of time
