code: synchronized void addProbesByListener(ProbeListener listener, Collection<ProbeImpl> probes) {
          Set<ProbeImpl> listenerProbes = probesByListener.get(listener);
          if (listenerProbes == null) {
              listenerProbes = new HashSet<ProbeImpl>();
              probesByListener.put(listener, listenerProbes);
          }
          listenerProbes.addAll(probes);
      }
docs: Associate the specified collection of probes with the specified listener.
  
  @param listener the listener that probes are fired to
  @param probes the probes fired to the listener