Thread "out-of-synch" 错误

debug一段代码的时候eclipse里出现：

    The out of synch notification in the debug view means that the code in the VMis not the same as the code in the workspace.At this time, our resolution is at the type level. If a type has changed inthe workspace but that change is not present in the stack frame displayed inthe debug view, we show that it is "out of synch." Stack frames may get outof synch in three ways - the VM doesn't support hot code replace (HCR), aparticular attempt at HCR has failed (not all VMs support all redefinitions),or the HCR succeeded but the VM was unable to pop the frame running old code.This last case can occur, for example, when the type in which a main methodresides is successfully changed. The main method will display "out of synch"because the VM cannot pop the main method from the stack until the programexits.    We cannot know what code is executing in a running thread, so the best thatwe can do is to say that a running thread "may be out of synch" after an HCRfails. That is, it may or may not be running the code which wasn't updated.

可能是机器内存太小的原因，解决方法，重新发布工程，不行就重启tomcat和eclipse。