Catching java.lang.OutOfMemoryError?

Question

Documentation for java.lang.Error says:

An Error is a subclass of Throwable that indicates serious problems that a reasonable application

Answer 1

1. Depends on how you define "good". We do that in our buggy web application and it does work most of the time (thankfully, now OutOfMemory doesn't happen due to an unrelated fix). However, even if you catch it, it still might have broken some important code: if you have several threads, memory allocation can fail in any of them. So, depending on your application there is still 10--90% chance of it being irreversibly broken.
2. As far as I understand, heavy stack unwinding on the way will invalidate so many references and thus free so much memory you shouldn't care about that.

EDIT: I suggest you try it out. Say, write a program that recursively calls a function that allocates progressively more memory. Catch OutOfMemoryError and see if you can meaningfully continue from that point. According to my experience, you will be able to, though in my case it happened under WebLogic server, so there might have been some black magic involved.