Logo Search packages:      
Sourcecode: poco version File versions  Download package

ActiveMethod.h
//
// ActiveMethod.h
//
// $Id: //poco/1.3/Foundation/include/Poco/ActiveMethod.h#3 $
//
// Library: Foundation
// Package: Threading
// Module:  ActiveObjects
//
// Definition of the ActiveMethod class.
//
// Copyright (c) 2004-2007, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
// 
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//


#ifndef Foundation_ActiveMethod_INCLUDED
#define Foundation_ActiveMethod_INCLUDED


#include "Poco/Foundation.h"
#include "Poco/ActiveResult.h"
#include "Poco/ActiveRunnable.h"
#include "Poco/ActiveStarter.h"
#include "Poco/AutoPtr.h"


namespace Poco {


template <class ResultType, class ArgType, class OwnerType, class StarterType = ActiveStarter<OwnerType> >
00054 class ActiveMethod
      /// An active method is a method that, when called, executes
      /// in its own thread. ActiveMethod's take exactly one
      /// argument and can return a value. To pass more than one
      /// argument to the method, use a struct.
      /// The following example shows how to add an ActiveMethod
      /// to a class:
      ///
      ///     class ActiveObject
      ///     {
      ///     public:
      ///         ActiveObject():
      ///             exampleActiveMethod(this, &ActiveObject::exampleActiveMethodImpl)
      ///         {
      ///         }
      ///
      ///         ActiveMethod<std::string, std::string, ActiveObject> exampleActiveMethod;
      ///
      ///     protected:
      ///         std::string exampleActiveMethodImpl(const std::string& arg)
      ///         {
      ///             ...
      ///         }
      ///     };
      ///
      /// And following is an example that shows how to invoke an ActiveMethod.
      ///
      ///     ActiveObject myActiveObject;
      ///     ActiveResult<std::string> result = myActiveObject.exampleActiveMethod("foo");
      ///     ...
      ///     result.wait();
      ///     std::cout << result.data() << std::endl;
      ///
      /// The way an ActiveMethod is started can be changed by passing a StarterType
      /// template argument with a corresponding class. The default ActiveStarter
      /// starts the method in its own thread, obtained from a thread pool.
      ///
      /// For an alternative implementation of StarterType, see ActiveDispatcher.
      ///
      /// For methods that do not require an argument or a return value, the Void
      /// class can be used.
{
public:
      typedef ResultType (OwnerType::*Callback)(const ArgType&);
      typedef ActiveResult<ResultType> ActiveResultType;
      typedef ActiveRunnable<ResultType, ArgType, OwnerType> ActiveRunnableType;

      ActiveMethod(OwnerType* pOwner, Callback method):
            _pOwner(pOwner),
            _method(method)
            /// Creates an ActiveMethod object.
      {
            poco_check_ptr (pOwner);
      }
      
00109       ActiveResultType operator () (const ArgType& arg)
            /// Invokes the ActiveMethod.
      {
            ActiveResultType result(new ActiveResultHolder<ResultType>());
            ActiveRunnableBase::Ptr pRunnable(new ActiveRunnableType(_pOwner, _method, arg, result));
            StarterType::start(_pOwner, pRunnable);
            return result;
      }
            
      ActiveMethod(const ActiveMethod& other):
            _pOwner(other._pOwner),
            _method(other._method)
      {
      }

      ActiveMethod& operator = (const ActiveMethod& other)
      {
            ActiveMethod tmp(other);
            swap(tmp);
            return *this;
      }

      void swap(ActiveMethod& other)
      {
            std::swap(_pOwner, other._pOwner);
            std::swap(_method, other._method);
      }

private:
      ActiveMethod();

      OwnerType* _pOwner;
      Callback   _method;
};



template <class ResultType, class OwnerType, class StarterType>
00147 class ActiveMethod <ResultType, void, OwnerType, StarterType>
      /// An active method is a method that, when called, executes
      /// in its own thread. ActiveMethod's take exactly one
      /// argument and can return a value. To pass more than one
      /// argument to the method, use a struct.
      /// The following example shows how to add an ActiveMethod
      /// to a class:
      ///
      ///     class ActiveObject
      ///     {
      ///     public:
      ///         ActiveObject():
      ///             exampleActiveMethod(this, &ActiveObject::exampleActiveMethodImpl)
      ///         {
      ///         }
      ///
      ///         ActiveMethod<std::string, std::string, ActiveObject> exampleActiveMethod;
      ///
      ///     protected:
      ///         std::string exampleActiveMethodImpl(const std::string& arg)
      ///         {
      ///             ...
      ///         }
      ///     };
      ///
      /// And following is an example that shows how to invoke an ActiveMethod.
      ///
      ///     ActiveObject myActiveObject;
      ///     ActiveResult<std::string> result = myActiveObject.exampleActiveMethod("foo");
      ///     ...
      ///     result.wait();
      ///     std::cout << result.data() << std::endl;
      ///
      /// The way an ActiveMethod is started can be changed by passing a StarterType
      /// template argument with a corresponding class. The default ActiveStarter
      /// starts the method in its own thread, obtained from a thread pool.
      ///
      /// For an alternative implementation of StarterType, see ActiveDispatcher.
      ///
      /// For methods that do not require an argument or a return value, simply use void.
{
public:
      typedef ResultType (OwnerType::*Callback)(void);
      typedef ActiveResult<ResultType> ActiveResultType;
      typedef ActiveRunnable<ResultType, void, OwnerType> ActiveRunnableType;

      ActiveMethod(OwnerType* pOwner, Callback method):
            _pOwner(pOwner),
            _method(method)
            /// Creates an ActiveMethod object.
      {
            poco_check_ptr (pOwner);
      }
      
00201       ActiveResultType operator () (void)
            /// Invokes the ActiveMethod.
      {
            ActiveResultType result(new ActiveResultHolder<ResultType>());
            ActiveRunnableBase::Ptr pRunnable(new ActiveRunnableType(_pOwner, _method, result));
            StarterType::start(_pOwner, pRunnable);
            return result;
      }
            
      ActiveMethod(const ActiveMethod& other):
            _pOwner(other._pOwner),
            _method(other._method)
      {
      }

      ActiveMethod& operator = (const ActiveMethod& other)
      {
            ActiveMethod tmp(other);
            swap(tmp);
            return *this;
      }

      void swap(ActiveMethod& other)
      {
            std::swap(_pOwner, other._pOwner);
            std::swap(_method, other._method);
      }

private:
      ActiveMethod();

      OwnerType* _pOwner;
      Callback   _method;
};


} // namespace Poco


#endif // Foundation_ActiveMethod_INCLUDED

Generated by  Doxygen 1.6.0   Back to index