TeQuerierDBStr2.h

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/************************************************************************************
TerraLib - a library for developing GIS applications.
Copyright © 2001-2007 INPE and Tecgraf/PUC-Rio.

This code is part of the TerraLib library.
This library is free software; you can redistribute it and/or
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*************************************************************************************/
/*! \file TeQuerierDBStr2.h
        \brief This file contains a mechanism named "TeQuerierDBStr2" that is 
        responsible for loading spatio-temporal elements from a TerraLib database. 
*/

#ifndef  __TERRALIB_INTERNAL_QUERIER_DBSTR2_H
#define  __TERRALIB_INTERNAL_QUERIER_DBSTR2_H

#include "TeQuerierDB.h"
#include "TeTemporalSeries.h"

/*! \class TeQuerierDBStr2
        \brief A class responsible for loading spatio-temporal elements from a TerraLib database.

        This class implements a mechanism that is responsible for loading 
        spatio-temporal elements from a TerraLib database, following a specific strategy (Strategy 2). 
        Each spatio-temporal elements is represented through a TeSTInstance class. 
        This class is internally used by the factory of queriers. It should NOT be used 
        by anyone. This Strategy 2 works with simple chronon, without geometry, 
        theme with collection table and existence operator in the DBMS.  

        \sa
        TeQuerierDB TeQuerierParams TeSTInstance 
*/

class TL_DLL TeQuerierDBStr2: public TeQuerierDB
{
private:
        int                             timeFramePortal_;  // the time frame appointed by the portal 
        TeTSEntry               TSEntry_;
        
        /* @name Internal functions to initialize portals */
        //@{
        bool initPortal(TeTSEntry* ent=0); 
        //@}

        //! Internal function to fill STO
        bool fillSTO(TeSTInstance& sto); 
        
public:
        //! Constructor
        TeQuerierDBStr2(TeQuerierParams* params): 
                TeQuerierDB(params), 
                timeFramePortal_(-1)
        {} 

        //! Loads the instances
        bool loadInstances(TeTSEntry* ent=0); 

        //! Returns each loaded STO
        bool fetchInstance(TeSTInstance&  sto); 

        //! Returns the number of instances 
        int  numElemInstances();
};

/*! \class TeQuerierDBStr2Factory
        \brief A class that define a factory to build a querier strategy (strategy 2) from TerraLib database.

        \sa
        TeQuerierImplFactory TeQuerierDBStr2
*/
class TL_DLL TeQuerierDBStr2Factory : public TeQuerierImplFactory
{
public:
        //! Constructor
        TeQuerierDBStr2Factory(const string& name) : TeQuerierImplFactory(name) {}

        //! Builds a database querier
        virtual TeQuerierImpl* build (const TeQuerierParams& arg)
        {  
                TeQuerierParams* tempArg = new TeQuerierParams();
                *tempArg = arg;
                return new TeQuerierDBStr2(tempArg); 
        }
};

//! Creates a static factory to build TeQuerierDBStr2 
namespace 
{
  static TeQuerierDBStr2Factory querierDBStr2("querierDBStr2");
};

#endif

---