code: public void removeTangoArchiveListener(ITangoArchiveListener listener, String attrName)
              throws DevFailed {
          synchronized (moni) {
              TangoArchive tangoArchive;
              String key = deviceName+"/"+attrName;
              if ((tangoArchive = tango_archive_source.get(key)) != null)
                  tangoArchive.removeTangoArchiveListener(listener);
          }
      }
docs: =======================================================================