[477205] Fix potential ClassCastException

Avoid unchecked cast in GEF's getCurrentConstraintFor() by inlining a
slightly more robust version in our overridden method.

Bug: 477205
Change-Id: I4da768b0f1e83679334929fe25907036c1a75e37
Cherry-picks: cb3b9eef35b9eea2cd9000a0c12fcf157c9f1111
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>

1 files changed, 8 insertions, 10 deletions

diff --git a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/graphical/edit/policies/AirXYLayoutEditPolicy.java b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/graphical/edit/policies/AirXYLayoutEditPolicy.java
index be83fe5554..6d7f735cd6 100644
--- a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/graphical/edit/policies/AirXYLayoutEditPolicy.java
+++ b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/graphical/edit/policies/AirXYLayoutEditPolicy.java
@@ -14,6 +14,7 @@ import java.util.List;
 
 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.draw2d.FigureCanvas;
+import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.geometry.Dimension;
 import org.eclipse.draw2d.geometry.Point;
 import org.eclipse.draw2d.geometry.Rectangle;
@@ -258,18 +259,15 @@ public class AirXYLayoutEditPolicy extends XYLayoutEditPolicy {
         return element instanceof DNodeContainer && new DNodeContainerExperimentalQuery((DNodeContainer) element).isRegionContainer();
     }
 
-    /**
-     * {@inheritDoc}
-     * 
-     * @see org.eclipse.gef.editpolicies.XYLayoutEditPolicy#getCurrentConstraintFor(org.eclipse.gef.GraphicalEditPart)
-     */
     @Override
-    protected Rectangle getCurrentConstraintFor(final GraphicalEditPart child) {
-        Rectangle result = super.getCurrentConstraintFor(child);
-        if (result == null) {
-            result = new Rectangle(0, 0, -1, -1);
+    protected Rectangle getCurrentConstraintFor(GraphicalEditPart child) {
+        IFigure fig = child.getFigure();
+        Object constraint = fig.getParent().getLayoutManager().getConstraint(fig);
+        if (constraint instanceof Rectangle) {
+            return (Rectangle) constraint;
+        } else {
+            return new Rectangle(0, 0, -1, -1);
         }
-        return result;
     }
 
     /**