public void undo() {
    final Collection<CyNetworkView> views = networkViewManager.getNetworkViews(network);
    CyNetworkView view = null;
    if (views.size() != 0) view = views.iterator().next();

    networkCenterX = view.getVisualProperty(NETWORK_CENTER_X_LOCATION);
    networkCenterY = view.getVisualProperty(NETWORK_CENTER_Y_LOCATION);
    networkCenterZ = view.getVisualProperty(NETWORK_CENTER_Z_LOCATION);
    networkScaleFactor = view.getVisualProperty(NETWORK_SCALE_FACTOR);

    final Collection<View<CyNode>> nodeViews = view.getNodeViews();
    nodesAndLocations = new WeakHashMap<CyNode, NodeLocations>(nodeViews.size());
    for (final View<CyNode> nodeView : nodeViews)
      nodesAndLocations.put(nodeView.getModel(), new NodeLocations(nodeView));

    networkViewManager.destroyNetworkView(view);
  }
  private void checkView(final CyNetworkView view) {
    assertEquals(Color.BLACK, view.getVisualProperty(NETWORK_BACKGROUND_PAINT));
    assertEquals(new Double(639.0d), view.getVisualProperty(NETWORK_WIDTH));
    assertEquals(new Double(624.0d), view.getVisualProperty(NETWORK_HEIGHT));
    assertEquals(
        new Double(3091.2991395970175d), view.getVisualProperty(NETWORK_CENTER_X_LOCATION));
    assertEquals(new Double(3610.396738076269d), view.getVisualProperty(NETWORK_CENTER_Y_LOCATION));
    assertEquals(new Double(0.05044042295795177d), view.getVisualProperty(NETWORK_SCALE_FACTOR));

    // All nodes have the same size, border and shape
    final View<CyNode> nv = view.getNodeView(view.getModel().getNodeList().iterator().next());
    assertEquals(80, nv.getVisualProperty(NODE_WIDTH).intValue());
    assertEquals(30, nv.getVisualProperty(NODE_HEIGHT).intValue());
    assertEquals(NodeShapeVisualProperty.ROUND_RECTANGLE, nv.getVisualProperty(NODE_SHAPE));
    assertEquals(180, nv.getVisualProperty(NODE_TRANSPARENCY).intValue());
    assertEquals(2, nv.getVisualProperty(NODE_BORDER_WIDTH).intValue());
    assertEquals(LineTypeVisualProperty.SOLID, nv.getVisualProperty(NODE_BORDER_LINE_TYPE));
    assertEquals(new Color(153, 153, 255), nv.getVisualProperty(NODE_BORDER_PAINT));
    assertEquals(255, nv.getVisualProperty(NODE_BORDER_TRANSPARENCY).intValue());
    assertEquals(new Color(255, 255, 255), nv.getVisualProperty(NODE_LABEL_COLOR));
    assertEquals(255, nv.getVisualProperty(NODE_LABEL_TRANSPARENCY).intValue());

    // All edges have the same width and other properties
    final View<CyEdge> ev = view.getEdgeView(view.getModel().getEdgeList().iterator().next());
    assertEquals(new Double(1.0), ev.getVisualProperty(EDGE_WIDTH));
    assertEquals(255, ev.getVisualProperty(EDGE_TRANSPARENCY).intValue());
    assertEquals(ArrowShapeVisualProperty.NONE, ev.getVisualProperty(EDGE_SOURCE_ARROW_SHAPE));
    assertEquals(ArrowShapeVisualProperty.NONE, ev.getVisualProperty(EDGE_TARGET_ARROW_SHAPE));
  }