The fields of this class appear to be accessed inconsistently with respect to synchronization. This bug report indicates that the bug pattern detector judged that
A typical bug matching this bug pattern is forgetting to synchronize one of the methods in a class that is intended to be thread-safe.
Note that there are various sources of inaccuracy in this detector; for example, the detector cannot statically detect all situations in which a lock is held. Also, even when the detector is accurate in distinguishing locked vs. unlocked accesses, the code in question may still be correct.