Game crashed while using hotkeys to craft a new pick.

I was quickly crafting a stone pick and swapping the wood pick on my bar with it. I pulled the new pick out of the crafting table with a number key, then used another number key to swap it's place with the old pick. My mouse moved to one of the corners of the screen while I was swapping the picks (I was performing the actions very quickly), and the game crashed. When I logged back in to the save, the new pick and the items used to craft it were gone.

The game was in fullscreen mode via the F11 key.

What I expected to happen was...:
The game to continue operating?

What actually happened was...:
The game did not continue operating. It had a good run, but ultimately, the IndexOutOfBoundsException got the best of it. Whatever that means.

Steps to Reproduce:
I can't get it to happen again. Sorry. D: Hope the crash report has enough info.

[Edit] I just noticed that my Java was out of date. Updated it, maybe that was the problem. Maybe-sorry for the potentially-false alarm!