Returns the blocker object supplied to the most recent
invocation of a park method that has not yet unblocked, or null
if not blocked. The value returned is just a momentary
snapshot -- the thread may have since unblocked or blocked on a
different blocker object.
@param t the thread
@return the blocker
@throws NullPointerException if argument is null
Returns the blocker object supplied to the most recent invocation of a park method that has not yet unblocked, or null if not blocked. The value returned is just a momentary snapshot -- the thread may have since unblocked or blocked on a different blocker object.
@param t the thread @return the blocker @throws NullPointerException if argument is null