server.start();
ret.register(qid1, qid1Dir.getPath());
InetSocketAddress addr = server.getBindAddress();
assertDataRetrival(qid1, addr.getPort(), watermark1);
ret.unregister(qid1);
assertDataRetrival(qid1, addr.getPort(), watermark1);
}
private static void assertDataRetrival(QueryUnitId id, int port,
String watermark) throws IOException {