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cObjRef.cpp

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/******************************************************************************/
/*                                                                            */
/* POLiTe - Persistent Object Library Test                                    */
/*                                        Ph.D. Thesis by Mgr. Michal Kopecky */
/*                                                                            */
/* Charles University Prague                                                  */
/*                                                                            */
/******************************************************************************/
/*                                                                            */
/* File name: ...                                                             */
/* Module: ......                                                             */
/*                                                                            */
/******************************************************************************/

// Own Header
#include <cObjRef.h>                                    // ObjRef class header

// Other POLiTe Header(s)
#include <cRefBase.h>
#include <cProtoBase.h>
#include <cQuery.h>
#include <cConnection.h>

//  An Object is a common ancestor class of RefBase and
//  Object. It is virtual class.
//      Object is a simple object which consists of some methods,
//      that in its successors must be redefined.
//  It was created to resolve some problems with RefBase and
//      Object (and ResultBase as well).
//

// Object constructor:
// Create the Object object with the appropriate initialization.

ObjRef::ObjRef()
{
        _Strategies =
                DEFAULT_LOCKING_STRATEGY
                | DEFAULT_UPDATING_STRATEGY
                | DEFAULT_WAITING_STRATEGY
                | DEFAULT_READING_STRATEGY;
        _Connection = NULL;
        #ifdef GC_OBJRF_TRACE
        logmsg("ObjRef::ObjRef() invoked and finished");
        #endif
}

// Object destructor:
// Delete the Object object with the appropriate de-initialization.

ObjRef::~ObjRef()
{
        #ifdef GC_OBJRF_TRACE
        logmsg("ObjRef::~ObjRef() invoked and finished");
        #endif
}

char *ObjRef::_Where() const
//Returns Where clause in SQL select for referenced object
{
        if (Prototype() == NULL)
                return NONE._Where();
        char *_where = NULL;
        char *_columns = StrCpy(_columns = NULL, Prototype()->KeySelect());
        char *_values = _KeyValues();
        char *_1column = NULL;
        char *_1value = NULL;
        const char *delim = "";
        while (StrSplit(_columns,',',_1column) && StrSplit(_values,',',_1value))
        {
                StrDecode(_1value);
                StrCat(_where,6,delim,"(",_1column," = ",_1value,")");
                delim = " AND ";
                StrFree(_1column);
                StrFree(_1value);
        };
        StrFree(_columns);
        StrFree(_values);
        return _where;
};

bool ObjRef::IsAncestor(
  const ObjRef &descendant
  ) const
        // Returns if *this Object is ancestor
        // of *descendant Object
{
        return (this->Prototype())>=(descendant.Prototype());
};

// returns oid of the object referenced by the database pointer
// and vice versa
// Usefull for representing pointers to objects between application classes

/*
long int ObjRef::_PtrToOid(
        const ObjRef &ref
   ) const
{
        if (ref.Prototype()->IsPersistentObject())
                return StrToLong(ref.SelectKeyValues());
        return 0;
};
*/

/*
RefBase ObjRef::_OidToPtr(
        const long int oid,
        class ProtoBase *prot
        ) const
{

        if (oid <= 0)
                return (RefBase &)DBNULL;
        else
        {
                RefBase result(Connection(),prot,LongToStr(oid));
                result.Virtualise();
                return result;
        };
};
*/

/*
Object *ObjRef::_OidToMemPtr(
        const long int oid,
   class ProtoBase *prot
        ) const
{

        if (oid <= 0)
                return NULL;
   else
   {
        RefBase result(Connection(),prot,LongToStr(oid));
      result.Virtualise();
                return &(result.ReferencedObject());
   };
};
*/

// Set corresponging patrs of attribute _Strategies
// that holds all concurency strategies
bool ObjRef::SetUpdatingStrategy(enum UpdatingStrategy anUpdatingStrategy)
{
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetUpdatingStrategy(...) invoked");
        #endif
        switch (anUpdatingStrategy)
        {
                case US_Current:
                        break;
                case US_Inherited:
                        _Strategies = _Strategies & ~US_MASK | (unsigned int)(_Connection ? _Connection->CurrentUpdatingStrategy() : DEFAULT_UPDATING_STRATEGY);
                        break;
                case US_Default:
                        _Strategies = _Strategies & ~US_MASK | DEFAULT_UPDATING_STRATEGY;
                        break;
                default:
                        _Strategies = _Strategies & ~US_MASK | (unsigned int)anUpdatingStrategy;
        };
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetUpdatingStrategy(...) finished");
        #endif
        return true;
};
bool ObjRef::SetWaitingStrategy(enum WaitingStrategy aWaitingStrategy)
{
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetWaitingStrategy(...) invoked");
        #endif
        switch (aWaitingStrategy)
        {
                case WS_Current:
                        break;
                case WS_Inherited:
                        _Strategies = _Strategies & ~WS_MASK | (unsigned int)(_Connection ? _Connection->CurrentWaitingStrategy() : DEFAULT_WAITING_STRATEGY);
                        break;
                case WS_Default:
                        _Strategies = _Strategies & ~WS_MASK | DEFAULT_WAITING_STRATEGY;
                        break;
                default:
                        _Strategies = _Strategies & ~WS_MASK | (unsigned int)aWaitingStrategy;
        };
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetWaitingStrategy(...) finished");
        #endif
        return true;
};
bool ObjRef::SetLockingStrategy(enum LockingStrategy aLockingStrategy)
{
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetLockingStrategy(...) invoked");
        #endif
        switch (aLockingStrategy)
        {
                case LS_Current:
                        break;
                case LS_Inherited:
                        _Strategies = _Strategies & ~LS_MASK | (unsigned int)(_Connection ? _Connection->CurrentLockingStrategy() : DEFAULT_LOCKING_STRATEGY);
                        break;
                case LS_Default:
                        _Strategies = _Strategies & ~LS_MASK | DEFAULT_LOCKING_STRATEGY;
                        break;
                default:
                        _Strategies = _Strategies & ~LS_MASK | (unsigned int)aLockingStrategy;
        };
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetLockingStrategy(...) finished");
        #endif
        return true;
};
bool ObjRef::SetReadingStrategy(enum ReadingStrategy aReadingStrategy)
{
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetReadingStrategy(...) invoked");
        #endif
        switch (aReadingStrategy)
        {
                case RS_Current:
                        break;
                case RS_Inherited:
                        _Strategies = _Strategies & ~RS_MASK | (unsigned int)(_Connection ? _Connection->CurrentReadingStrategy() : DEFAULT_READING_STRATEGY);
                        break;
                case RS_Default:
                        _Strategies = _Strategies & ~RS_MASK | DEFAULT_READING_STRATEGY;
                        break;
                default:
                        _Strategies = _Strategies & ~RS_MASK | (unsigned int)aReadingStrategy;
        };
        #ifdef C_OBJREF_TRACE
                logmsg("bool ObjRef::SetReadingStrategy(...) finished");
        #endif
        return true;
};

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