[vtkusers] How to use vtkPanel.

[Said.]

I still have difficulties to use vtkPanel and vtkCanvas classes. I'm
using vtk4.2. When having a look in vtk.jar, it seems that
vtkPanel.class and vtkCanvas aren't included in the package. Sources
files (vtkPanel.jar and vtkCanvas.java ) are located in
VTK_DIR/Wrapping/Java/vtk/ directory. I compile them succefully and use
vtkPanel to compile SimpleVTK.java file. Compilation is done succefully
but when running, I got only a window with the "Exit" button. 

I hope get some help.