In the App Engine docs, what is the ellipsis (
public MessageBuilder withRecipientJids(JID... recipientJids)
Those are Java varargs. They let you pass any number of objects of a specific type (in this case they are of type JID).
In your example, the following function calls would be valid:
MessageBuilder msgBuilder; //There should probably be a call to a constructor here ;) MessageBuilder msgBuilder2; msgBuilder.withRecipientJids(jid1, jid2); msgBuilder2.withRecipientJids(jid1, jid2, jid78_a, someOtherJid);