There was some drama about China possibly obtaining US stealth technology during Yugoslavia. There is an even more crazy conspiracy theory going on that this is why we bombed their embassy.
The Yugoslavian incident involved an F-117 -- completely different low observable technology than that used in the F-22/J-20/etc.
The mumblings I've heard is that the Chinese stole blueprints from the F-22 project. I don't have a URL handy at the moment, as I'm not near a web browser.
Besides, you can Google a sized-referenced picture of an F-22 from every angle. It's a relatively well-documented airframe.
