Synchronizes a group of threads.
More...
#include <jem/util/Barrier.h>
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| | Barrier (int n) |
| | Constructs a new barrier instance. More...
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| | ~Barrier () |
| | Destroys this barrier instance. More...
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| int | wait () |
| | Suspends the current thread until the last thread has called this function. More...
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| int | size () const |
| | Returns the number of threads that synchronize on this barrier. More...
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The Barrier class can be used to synchronize a group of threads. It provides a member function, named wait(), that suspends the calling thread. The threads are resumed when the last thread in the group calls the wait() member function.
- See also
Thread, Mutex, Monitor.
| jem::util::Barrier::Barrier |
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int |
n | ) |
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explicit |
Constructs a Barrier object that can be used to synchronize n threads.
- Parameters
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| n | - the number of threads that will synchronize on this Barrier object. |
- Precondition
n > 0
- Postcondition
this->size() == n
| jem::util::Barrier::~Barrier |
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Destroys this Barrier object. Suspended threads (that have called the member function wait) will not (and thus never) be resumed.
| int jem::util::Barrier::wait |
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If n is the size of this Barrier, then the first (n - 1) threads calling this member function will be suspended. They will be resumed when the n-th thread calls this function. The n-th call of this function also resets this Barrier object so that it can be used to synchronize the next n threads calling this function.
- Returns
LAST_THREAD when this member is called by the last thread (the n-th thread). Else, an integer different from LAST_THREAD is returned.
- Exceptions
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| CancelledException | - when a suspended thread is cancelled. Note that cancelling a suspended thread will not affect the normal operation of a Barrier object. That is, all suspended threads will be resumed by the last thread calling the wait function, even if one of the suspended threads is cancelled. |
| int jem::util::Barrier::size |
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| ) |
const |
Returns the number of threads that synchronize on this Barrier object.
- Returns
- The number of threads that synchronize on this barrier.
| const int jem::util::Barrier::LAST_THREAD |
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static |
An integer constant that is returned by the wait() member function when it is called by the last thread in the group of threads that synchronizes on this Barrier object.
