ThreadController.h

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//# Copyright (C) 2009
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 of the License, or (at your
//# option) any later version.
//#
//# This library is distributed in the hope that it will be useful, but WITHOUT
//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
//# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//#        Internet email: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
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//#

#ifndef THREADCONTROLLER_H_
#define THREADCONTROLLER_H_

#include <plotms/Threads/ThreadCommunication.h>

namespace casa {

//# Forward declarations.
class ProgressMonitor;
class BackgroundThread;
class PlotMSPlot;

// Typedefs for using post-thread methods.
// <group>
typedef void* PMSPTObject;
typedef void PMSPTMethod(PMSPTObject, bool);
// </group>

class ThreadController : public ThreadCommunication {
public:
        // Constructor which takes the progress widget to use, and an optional
        // post-thread method that should be called when the thread is finished.
        ThreadController(ProgressMonitor* progress,
                        PMSPTMethod postThreadMethod = NULL,
                        PMSPTObject postThreadObject = NULL);

        virtual ~ThreadController();

        //***********************************************************************
        //            Thread Communication Interface
        //***********************************************************************

        //Worker classes can store and error message.
        virtual void setError( const casacore::String& errorMessage );
        // Allows the cache to set the status.
        virtual void setStatus(const casacore::String& status);
        virtual void setProgress(unsigned int progress);
        virtual void finished( );
        // These signals are used to update the QtProgressWidget across different
        // threads.  They shouldn't need to be used by other classes, even
        // children.
        // <group>
        virtual void initializeProgress(const casacore::String& operationName);
        virtual void setProgress(unsigned int progress, const casacore::String& status);
        virtual void finishProgress();

        // </group>

        // Work classes can specify whether they support background operation, pause/resume,
        //and cancelling.
        virtual void setAllowedOperations(bool background, bool pauseResume, bool cancel);

        //Callback for classes doing the work to check whether they should
        //cancel what they are doing or not.
        virtual bool wasCanceled() const;

        //********************************************************************
        //                 Thread Control
        //********************************************************************

        //Store the thread that will be doing the work
        void setWorkThread( BackgroundThread* workThread );

        // For when the user requests "background" for the thread.
        virtual void background();

        // For when the user requests "pause" for the thread.
        virtual void pause();

        // For when the user requests "resume" for the thread.
        virtual void resume();

        // For when the user requests "cancel" for the thread.
        virtual void cancel();

        // Executes the post-thread method as needed.  Does nothing if a
        // post-thread method was not set in the constructor.
        virtual void postThreadMethod();

        //Returns the result of the background operation.
        bool getResult() const;

        //Returns any error from the background operation.
        casacore::String getError() const;
        bool isErrorWarning() const;
        casacore::String getErrorTitle() const;
        PlotMSPlot* getPlot();
protected:

        //Starts the thread
        void startThread();

        // Flag for whether thread was canceled or not.
        volatile bool wasCanceled_;

        //Holds error messages
        casacore::String error;
        casacore::String errorTitle;
        bool errorWarning;



        // Progress widget.
        ProgressMonitor* itsProgressWidget_;

        // Method/Object to run when thread is finished.
        // <group>
        PMSPTMethod* itsPostThreadMethod_;
        PMSPTObject itsPostThreadObject_;
        // </group>


private:
        ThreadController( const ThreadController& controller );
        ThreadController operator=( const ThreadController& other );

        BackgroundThread* bgThread;

};

} /* namespace casa */
#endif /* THREADCONTROLLER_H_ */