Threads and Locks - The Java Language Specification - page 568

Additionally, if there exists some object m whose wait set contains u , then u is removed
from m 's wait set. This enables u to resume in a wait action, in which case this wait will,
after re-locking m 's monitor, throw InterruptedException .
Invocations of Thread.isInterrupted can determine a thread's interruption status. The static
method Thread.interrupted may be invoked by a thread to observe and clear its own interrup-
tion status.
17.2.4. Interactions of Waits, Notification, and Interruption
The above specifications allow us to determine several properties having to do with the in-
teraction of waits, notification, and interruption.
If a thread is both notified and interrupted while waiting, it may either:
• return normally from wait , while still having a pending interrupt (in other words, a
call to Thread.interrupted would return true)
• return from wait by throwing an InterruptedException
The thread may not reset its interrupt status and return normally from the call to wait .
Similarly, notifications cannot be lost due to interrupts. Assume that a set s of threads is in
the wait set of an object m , and another thread performs a notify on m . Then either:
• at least one thread in s must return normally from wait , or
• all of the threads in s must exit wait by throwing InterruptedException
Note that if a thread is both interrupted and woken via notify , and that thread returns from
wait by throwing an InterruptedException , then some other thread in the wait set must be noti-
fied.
17.3. Sleep and Yield
Thread.sleep causes the currently executing thread to sleep (temporarily cease execution) for
the specified duration, subject to the precision and accuracy of system timers and sched-
ulers. The thread does not lose ownership of any monitors, and resumption of execution
will depend on scheduling and the availability of processors on which to execute the thread.
It is important to note that neither Thread.sleep nor Thread.yield have any synchronization se-
mantics. In particular, the compiler does not have to flush writes cached in registers out to
shared memory before a call to Thread.sleep or Thread.yield , nor does the compiler have to re-
load values cached in registers after a call to Thread.sleep or Thread.yield .