code: public ArrayList<Long> serviceName_tcp_frontend_GET(String serviceName, Long defaultFarmId, String port, String zone) throws IOException {
  		String qPath = "/ipLoadbalancing/{serviceName}/tcp/frontend";
  		StringBuilder sb = path(qPath, serviceName);
  		query(sb, "defaultFarmId", defaultFarmId);
  		query(sb, "port", port);
  		query(sb, "zone", zone);
  		String resp = exec(qPath, "GET", sb.toString(), null);
  		return convertTo(resp, t2);
  	}
docs: TCP frontends for this iplb
  
  REST: GET /ipLoadbalancing/{serviceName}/tcp/frontend
  @param defaultFarmId [required] Filter the value of defaultFarmId property (=)
  @param port [required] Filter the value of port property (like)
  @param zone [required] Filter the value of zone property (=)
  @param serviceName [required] The internal name of your IP load balancing