if (connection.isAnonymous()) {
throw new IllegalStateException("Anonymous users can't have a roster.");
}
// Create and send roster entry creation packet.
RosterPacket rosterPacket = new RosterPacket();
rosterPacket.setType(IQ.Type.SET);
RosterPacket.Item item = new RosterPacket.Item(user, name);
if (groups != null) {
for (String group : groups) {
if (group != null && group.trim().length() > 0) {
item.addGroupName(group);
}
}
}
rosterPacket.addRosterItem(item);
// Wait up to a certain number of seconds for a reply from the server.
PacketCollector collector = connection.createPacketCollector(
new PacketIDFilter(rosterPacket.getPacketID()));
connection.sendPacket(rosterPacket);
IQ response = (IQ) collector.nextResult(SmackConfiguration.getPacketReplyTimeout());
collector.cancel();
if (response == null) {
throw new XMPPException("No response from the server.");