Here are the FindBugs analysis results files for my recent use of obligation analysis to look for unclosed stream bugs in Vuze and jEdit:
I classified the warnings as NEEDS_ANALYSIS if I considered the code apparently correct, and the warning could be avoided through the use of annotations (@WillClose, @WillCloseWhenClosed, etc.) These were cases where if a called method (or object) failed to close the stream, then there truly would be a bug.
I classified warnings as SHOULD_FIX if I considered that it was possible for the code to fail to close a stream.
I classified the warnings as ANALYSIS_ERROR if the warning was completely erroneous.