# HG changeset patch
# User Peter Hofer <peter.hofer@jku.at>
# Date 1320244660 -3600
# Node ID e43bd78ca3a4f5cc6fecc7cea9562342ee357cb3
# Parent  5a1a05d3a30b90c4edb7da4e718eacf3f11d2851
IdealGraphVisualizer: the context menu of graph nodes includes submenus for predecessors and successors. Recursively building them ahead of time can incur heavy delays even with limited recursion depth. Instead, build these menus on demand, i.e. when the user opens a particular submenu.

diff -r 5a1a05d3a30b -r e43bd78ca3a4 src/share/tools/IdealGraphVisualizer/View/src/com/sun/hotspot/igv/view/widgets/FigureWidget.java
--- a/src/share/tools/IdealGraphVisualizer/View/src/com/sun/hotspot/igv/view/widgets/FigureWidget.java	Wed Nov 02 14:09:40 2011 +0100
+++ b/src/share/tools/IdealGraphVisualizer/View/src/com/sun/hotspot/igv/view/widgets/FigureWidget.java	Wed Nov 02 15:37:40 2011 +0100
@@ -43,6 +43,8 @@
 import javax.swing.BorderFactory;
 import javax.swing.JMenu;
 import javax.swing.JPopupMenu;
+import javax.swing.event.MenuEvent;
+import javax.swing.event.MenuListener;
 import org.netbeans.api.visual.action.PopupMenuProvider;
 import org.netbeans.api.visual.action.WidgetAction;
 import org.netbeans.api.visual.model.ObjectState;
@@ -61,7 +63,6 @@
 public class FigureWidget extends Widget implements Properties.Provider, PopupMenuProvider, DoubleClickHandler {
 
     public static final boolean VERTICAL_LAYOUT = true;
-    public static final int DEPTH = 5;
     //public static final int MAX_STRING_LENGTH = 20;
     private static final double LABEL_ZOOM_FACTOR = 0.3;
     private static final double ZOOM_FACTOR = 0.1;
@@ -267,61 +268,84 @@
             getScene().getGraphics().setComposite(oldComposite);
         }
     }
-
+ 
     public JPopupMenu getPopupMenu(Widget widget, Point point) {
-        JPopupMenu m = diagramScene.createPopupMenu();
+        JPopupMenu menu = diagramScene.createPopupMenu();
+        menu.addSeparator();
 
         JMenu predecessors = new JMenu("Nodes Above");
-        addFigureToSubMenu(predecessors, getFigure(), false, DEPTH);
+        predecessors.addMenuListener(new NeighborMenuListener(predecessors, getFigure(), false));
+        menu.add(predecessors);
 
         JMenu successors = new JMenu("Nodes Below");
-        addFigureToSubMenu(successors, getFigure(), true, DEPTH);
+        successors.addMenuListener(new NeighborMenuListener(successors, getFigure(), true));
+        menu.add(successors);
 
-        m.addSeparator();
-        m.add(predecessors);
-        m.add(successors);
-        return m;
+        return menu;
     }
 
-    public void addFigureToSubMenu(JMenu subMenu, final Figure f, boolean successor, int depth) {
-        Set<Figure> set = f.getPredecessorSet();
-        if (successor) {
-            set = f.getSuccessorSet();
-        }
+    /**
+     * Builds the submenu for a figure's neighbors on demand.
+     */
+    private class NeighborMenuListener implements MenuListener {
 
-        int count = set.size();
-        if (set.contains(f)) {
-            count--;
+        private final JMenu menu;
+        private final Figure figure;
+        private final boolean successors;
+
+        public NeighborMenuListener(JMenu menu, Figure figure, boolean successors) {
+            this.menu = menu;
+            this.figure = figure;
+            this.successors = successors;
         }
 
-        for (Figure f2 : set) {
-            if (f2 == f) {
-                continue;
+        public void menuSelected(MenuEvent e) {
+            if (menu.getItemCount() > 0) {
+                // already built before
+                return;
+            }
+
+            Set<Figure> set = figure.getPredecessorSet();
+            if (successors) {
+                set = figure.getSuccessorSet();
             }
 
-            count--;
-            addFigureToMenu(subMenu, f2, successor, depth - 1);
-            if (count > 0) {
-                subMenu.addSeparator();
+            boolean first = true;
+            for (Figure f : set) {
+                if (f == figure) {
+                    continue;
+                }
+
+                if (first) {
+                    first = false;
+                } else {
+                    menu.addSeparator();
+                }
+
+                Action go = diagramScene.createGotoAction(f);
+                menu.add(go);
+
+                JMenu preds = new JMenu("Nodes Above");
+                preds.addMenuListener(new NeighborMenuListener(preds, f, false));
+                menu.add(preds);
+
+                JMenu succs = new JMenu("Nodes Below");
+                succs.addMenuListener(new NeighborMenuListener(succs, f, true));
+                menu.add(succs);
+            }
+
+            if (menu.getItemCount() == 0) {
+                menu.add("(none)");
             }
         }
-    }
 
-    public void addFigureToMenu(JMenu m, final Figure f, boolean successor, int depth) {
-        Action a = diagramScene.createGotoAction(f);
-        m.add(a);
-
-        if (depth > 0) {
-            String name = "Nodes Above";
-            if (successor) {
-                name = "Nodes Below";
-            }
-
-            JMenu subMenu = new JMenu(name);
-            addFigureToSubMenu(subMenu, f, successor, depth);
-            m.add(subMenu);
+        public void menuDeselected(MenuEvent e) {
+            // ignore
         }
 
+        public void menuCanceled(MenuEvent e) {
+            // ignore
+        }
     }
 
     public void handleDoubleClick(Widget w, WidgetAction.WidgetMouseEvent e) {