code: public static synchronized PortRange getTcpInstance() {
          if (tcpPortRange == null) {
              tcpPortRange = new PortRange();
              tcpPortRange.init(CoGProperties.getDefault().getTcpPortRange());
          }
          return tcpPortRange;
      }
docs: Returns PortRange instance for TCP listening sockets.
  If the tcp.port.range property is set, the class
  will be initialized with the specified port ranges.
  
  @return PortRange the default instace of this class.