"Java Platform SE Binary not responding". I keep losing worlds to this eventual message. I lose them as game play is painfully slow, maybe 2 minutes for a mouse move to activate. My solution has been to open a new world, 7 so far. That's an awful lot of work and play to have to dump and it's getting so I don't want to bother anymore.
When the world slows I know it's coming. When it's so bad I do a Ctrl-Alt-Del and End Task, then this message appears and that's the end, it won't open again, just get this message.
I may have blundered on a solution the last time.
I deleted the world and then started a new one inadvertently with the same name. I spawned recognized roughly where I was, and then spent my time finding my way back to my working locales (located by big created lava fall on coastal island). I played about two weeks until I got the message again (about an hour ago). I'm about to try this again, as I came here to see if there was a solution, so I'll post again to let you know if it works.