code: public synchronized void serverChanged(final HadoopServer location,
        final int type) {
  
      switch (type) {
        case ServerRegistry.SERVER_STATE_CHANGED: {
          this.provider.refresh(map.get(location));
          break;
        }
  
        case ServerRegistry.SERVER_ADDED: {
          DFSLocation dfsLoc = new DFSLocation(provider, location);
          map.put(location, dfsLoc);
          this.provider.refresh(this);
          break;
        }
  
        case ServerRegistry.SERVER_REMOVED: {
          map.remove(location);
          this.provider.refresh(this);
          break;
        }
      }
    }
docs: /* @inheritDoc