If I have three nodes (boxes), and I create an arrow to connect two of them, I can drag an arrows endpoint to another node. I want to stop this from happening, but don't want to stop the user having the ability to move the arrow around the nodes border using setAllowMoveStart/End(false). Is there any way I can do this? I don't think I want to use anchor points as that will mean it is stuck to a certain point on the node, and I want to allow the user to specify the location of the endpoint.

I tried writing some code to detect and prevent this from happening, but it doesn't seem to do anything:

            @Override
            public void itemModifying(ValidationEvent e) {
                if (e.getItem() instanceof Arrow) {
                    Arrow oArrow = (Arrow)e.getItem();
                    java.awt.geom.Point2D.Float oSource = oArrow.getControlPoints().get(0);
                    java.awt.geom.Point2D.Float oDestination = oArrow.getControlPoints().get(oArrow.getControlPoints().size() -1);
                    Node oFrom = oArrow.getOrigin();
                    Node oTo = oArrow.getDestination();

                    if ((oSource.getX() >= oFrom.getBounds().getX() && oSource.getX() <= oFrom.getBounds().getX() + oFrom.getBounds().getWidth()) &&
                        (oSource.getY() >= oFrom.getBounds().getY() && oSource.getY() <= oFrom.getBounds().getY() + oFrom.getBounds().getHeight())) {
                        //Ignore
                    } else {
                        double dNewX = oSource.getX();
                        double dNewY = oSource.getY();
                        if (oSource.getX() < oFrom.getBounds().getX()) { dNewX = oFrom.getBounds().getX(); }
                        if (oSource.getX() > oFrom.getBounds().getX() + oFrom.getBounds().getWidth()) { dNewX = oFrom.getBounds().getX() + oFrom.getBounds().getWidth(); }
                        if (oSource.getY() < oFrom.getBounds().getY()) { dNewY = oFrom.getBounds().getY(); }
                        if (oSource.getY() > oFrom.getBounds().getY() + oFrom.getBounds().getHeight()) { dNewY = oFrom.getBounds().getY() + oFrom.getBounds().getHeight(); }
                        oSource.setLocation(dNewX, dNewY);
                    }
                    //java.awt.geom.Point2D.Float oTemp = oArrow.getControlPoints().get(0); //Debugging
                    oArrow.setSnapToNodeBorder(false);
                    oArrow.updateFromPoints();
                    oArrow.setSnapToNodeBorder(true);
                    //oTemp = oArrow.getControlPoints().get(0); //Debugging
                }
            } 

The setValid(false) worked great Thanks!