code: public String getLabel(JComponent component) {
          String label = component2LabelMap.get(component);
          if (label != null) {
              return label;
          } else {
              return "";
          }
      }
docs: Gets the label for the specified component.
  
  @param component The component whose label is to be
  retrieved
  @return The label of the specified component, or an
  empty string if the component isn't held by this component node.