DatabaseManager.getCollection("xmldb:basex://<theserverip>:1984/wcs-collection",
So the reason is probably your server ip. Please note that the BaseX XML:DB API only works in embedded mode (using localhost).
I 've just tried the XQJ
xqjd.setProperty("serverName",
"http://<theserverip>:1984/wcs-collection/"); and I have an java.net.UnknownHostException.
XQJ should indeed communicate with the database server. Are you are that your server is running?
Best, Christian