OnixS C++ FIX Engine  4.9.0
API Documentation
SharedFuture< T > Class Template Reference

#include <OnixS/FIXEngine/Threading/Future.h>

Public Member Functions

 SharedFuture (const SharedFuture< T > &other) ONIXS_FIXENGINE_NOTHROW
SharedFuture< T > & operator= (const SharedFuture< T > &other) ONIXS_FIXENGINE_NOTHROW
Implementation::FutureGetReturn< T >::Type get () const
void swap (SharedFuture< T > &other) ONIXS_FIXENGINE_NOTHROW
void get () const
- Public Member Functions inherited from FutureBase
bool valid () const ONIXS_FIXENGINE_NOTHROW
ONIXS_FIXENGINE_API bool isReady () const
ONIXS_FIXENGINE_API bool hasValue () const
ONIXS_FIXENGINE_API bool hasException () const
ONIXS_FIXENGINE_API FutureStatus::Enum wait (int timeoutInMs=InfiniteTimeout) const


class Implementation::FutureHelper
class Implementation::PromiseBase

Additional Inherited Members

- Public Types inherited from FutureBase
enum  { InfiniteTimeout = -1 }
- Protected Member Functions inherited from FutureBase
 FutureBase ()
ONIXS_FIXENGINE_API FutureBaseoperator= (const FutureBase &other) ONIXS_FIXENGINE_NOTHROW
ONIXS_FIXENGINE_API FutureBase (const System::FutureSharedState *state) ONIXS_FIXENGINE_NOTHROW
ONIXS_FIXENGINE_API FutureBase (const System::FutureSharedState *state, moving_init_t) ONIXS_FIXENGINE_NOTHROW
ONIXS_FIXENGINE_API const FutureValuegetValue () const
ONIXS_FIXENGINE_API void getVoid () const

Detailed Description

template<typename T>
class OnixS::Threading::SharedFuture< T >

The class template Future provides a mechanism to access the result of asynchronous operations :

  • An asynchronous operation (e.g. created via Promise) can provide a Future object to the creator of that asynchronous operation (e.g. via Promise::getFuture).
  • The creator of the asynchronous operation can then use a variety of methods to query, wait for, or extract a value from Future. These methods may block if the asynchronous operation has not yet provided a value.
  • When the asynchronous operation is ready to send a result to the creator, it can do so by modifying shared state (e.g. via Promise::setValue) that is linked to the creator's Future.

Future is the synchronization object constructed around the receiving end of the Promise channel. It allows for the separation of the initiation of an operation and the act of waiting for its result.

Future is copyable and multiple SharedFuture objects may refer to the same shared state.

Unlike std::future, this implementation has an extended API, allowing you to query the state of SharedFuture. The internal implementation is lock-free; therefore, setting and polling states do not lead to blocking of threads and/or switching of an execution context.

Access to the same shared state from multiple threads is safe if each thread does it through its own copy of a SharedFuture object.
See also
http://en.cppreference.com/w/cpp/thread/shared_future .

Definition at line 253 of file Future.h.

Constructor & Destructor Documentation

SharedFuture ( )

Definition at line 256 of file Future.h.

SharedFuture ( const SharedFuture< T > &  other)

Copy constructor.

Definition at line 260 of file Future.h.

Member Function Documentation

Implementation::FutureGetReturn<T>::Type get ( ) const

Returns the result.

If the result is not ready, the method will block. When completes, it either returns a value or throws an exception.

This method waits until the Future has a valid result and retrieves it. It effectively calls wait() in order to wait for the result.

Ifan exception was stored in the shared state referenced by this Future (e.g. via a call to Promise::setException()) then that exception will be thrown.

Definition at line 288 of file Future.h.

void get ( ) const

Definition at line 313 of file Future.h.

SharedFuture<T>& operator= ( const SharedFuture< T > &  other)

Copy assignment.

Definition at line 264 of file Future.h.

void swap ( SharedFuture< T > &  other)

swaps two SharedFuture objects

Definition at line 294 of file Future.h.

Friends And Related Function Documentation

friend class Implementation::FutureHelper

Definition at line 308 of file Future.h.

friend class Implementation::PromiseBase

Definition at line 309 of file Future.h.

The documentation for this class was generated from the following file: