code: @Override
      public Collection<KamNode> getNodes(NodeFilter filter) {
          Set<KamNode> kamNodes = new LinkedHashSet<KamNode>();
          for (KamNode kamNode : idNodeMap.values()) {
  
              // Check for a node filter
              if (null != filter) {
                  if (!filter.accept(kamNode)) {
                      continue;
                  }
              }
              kamNodes.add(kamNode);
          }
          return kamNodes;
      }
docs: {@inheritDoc}