code: public String[] getPossibleTangoHosts(Database database) {
          String[] tangoHosts = null;
          try {
              DeviceData deviceData = database.command_inout("DbGetCSDbServerList");
              tangoHosts = deviceData.extractStringArray();
          } catch (DevFailed e) {
              String desc = e.errors[0].desc.toLowerCase();
              try {
                  if (desc.startsWith("command ") && desc.endsWith("not found")) {
                      tangoHosts = new String[]{database.getFullTangoHost()};
                  } else
                      System.err.println(e.errors[0].desc);
              } catch (DevFailed e2) {
                  System.err.println(e2.errors[0].desc);
              }
          }
          return tangoHosts;
      }
docs: ===================================================================