Cancellation and Shutdown - Java Concurrency in Practice - page 159

There is nothing in the API or language specification that ties interruption to any specific
cancellation semantics, but in practice, using interruption for anything but cancellation is fra-
gile and difficult to sustain in larger applications.
Each thread has a boolean interruptedstatus ; interrupting a thread sets its interrupted status to
true. Thread contains methods for interrupting a thread and querying the interrupted status
of a thread, as shown in Listing 7.4 . The interrupt method interrupts the target thread,
and isInterrupted returns the interrupted status of the target thread. The poorly named
static interrupted method clears the interrupted status of the current thread and returns
its previous value; this is the only way to clear the interrupted status.
Blocking library methods like Thread.sleep and Object.wait try to detect when a
thread has been interrupted and return early. They respond to interruption by clearing the in-
terrupted status and throwing InterruptedException , indicating that the blocking op-
eration completed early due to interruption. The JVM makes no guarantees on how quickly a
blocking method will detect interruption, but in practice this happens reasonably quickly.