Java SE (Java Platform, Standard Edition)

Good afternoon,

I'm trying to add JPanelA to JPanelB and make JPanelA completely fill the JPanelB (docking in VB.NET). Both panels use the FreeDesign Layout

After I add JPanelA I'm calling a method on it which does the following:

    public void DockInParent()
    {
        this.setBounds(this.getParent().getBounds());
        this.setSize(this.getParent().getSize());        
    }

JPanelA just isn't expanding to fill the bounds of its parent.

I know there must be a really simple way to do this. Can someone please give me a nudge in the right direction?