Java - SimpleFrame

I compiled files "SimpleFrame.java" and "SimpleViewer.java", but when I run, appear a blank screen and the messages:

Info: Load NativePaint lib...
Info: Loading NativePaint lib done
java.lang.UnsatisfiedLinkError: paint
at SimpleViewer.paint(Native Method)
at sun.awt.RepaintArea.paint(Unknown Source)
at sun.awt.windows.WComponentPeer.handleEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

Could anybody help me? What is wrong?
Do I need use "public native void paint(Graphics g);" function? Is there another way to show OpenCascade Viewer at screen?

Thanks
Cas