I was experiencing problems with Java a while ago and Unity was also affected by the problem. I had a wrong version of Java on my computer with the wrong graphics driver and only Java went wrong. It caused black screens in the GUI of Unity.
So I was wondering. Is the Unity IDE maybe written in Java to make it cross platform? Just curious.
Unity is written with a mixture of API's as well. http://answers.unity3d.com/questions/9675/is-unity-engine-written-in-monoc-or-c.html It was especially the Material previewer that broke down. So there should be more than just C#/C++.
– Marnix