secondo/Algebras/Network/NetworkManager.cpp

/*
This file is part of SECONDO.

Copyright (C) 2004, University in Hagen, Department of Computer Science,
Database Systems for New Applications.

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//paragraph [1] Title: [{\Large \bf \begin{center}] [\end{center}}]
//paragraph [10] Footnote: [{\footnote{] [}}]

1.1 Implementation of a Class Managing Networks


Mai-July 2007 Martin Scheppokat

Defines, includes, and constants

*/



#include "Algebras/TupleIdentifier/TupleIdentifier.h"
#include "NestedList.h"
#include "Algebras/BTree/BTreeAlgebra.h"
#include "Tools/Flob/DbArray.h"
#include "Algebras/Relation-C++/RelationAlgebra.h"
#include "Algebras/Spatial/SpatialAlgebra.h"
#include "NetworkAlgebra.h"
#include "NetworkManager.h"
#include "Symbols.h"

extern NestedList* nl;

using namespace network;
using namespace std;

void InitNetList(map<int,string> *netList)
{
  ListExpr xObjectList = SecondoSystem::GetCatalog()->ListObjects();
  xObjectList = nl->Rest(xObjectList);
  while(!nl->IsEmpty(xObjectList))
  {
    // Next element in list
    ListExpr xCurrent = nl->First(xObjectList);
    xObjectList = nl->Rest(xObjectList);

    // Type of object is at fourth position in list
    ListExpr xObjectType = nl->First(nl->Fourth(xCurrent));
    if(nl->IsAtom(xObjectType) &&
       nl->SymbolValue(xObjectType) == "network")
    {
      // Get name of the network
      ListExpr xObjectName = nl->Second(xCurrent);
      string strObjectName = nl->SymbolValue(xObjectName);

      Word xValue;
      bool bDefined;
      bool bOk = SecondoSystem::GetCatalog()->GetObject(strObjectName,
                                           xValue,
                                           bDefined);
      if(bDefined && bOk)
      {
        Network* pNetwork = (Network*)xValue.addr;
        netList->insert(pair<int,string>(pNetwork->GetId(), strObjectName));
        SecondoSystem::GetCatalog()->CloseObject(nl->SymbolAtom("network"),
                                      xValue);
      }
    }
  }
}

/*
Loads a network with a given id.

*/

Network* NetworkManager::GetNetworkNew(int in_iNetworkId,
                                       map<int,string> *netList)
{
  if (netList->empty()) InitNetList(netList);
  Network *pNetResult = 0;
  bool found = false;
  map<int,string>::iterator it = netList->find(in_iNetworkId);
  if (it != netList->end()) {
    found = true;
    string netobjname = (*it).second;
    if (netobjname != "")
    {
      Word xValue;
      bool bDefined;
      bool bOk = SecondoSystem::GetCatalog()->GetObject(netobjname,
                                           xValue,
                                           bDefined);
      if(bDefined && bOk) {
        pNetResult = (Network*)xValue.addr;
        return pNetResult;
      }
    }
  }
  ListExpr xObjectList = SecondoSystem::GetCatalog()->ListObjects();
  xObjectList = nl->Rest(xObjectList);
  while(!nl->IsEmpty(xObjectList))
  {
    // Next element in list
    ListExpr xCurrent = nl->First(xObjectList);
    xObjectList = nl->Rest(xObjectList);

    // Type of object is at fourth position in list
    ListExpr xObjectType = nl->First(nl->Fourth(xCurrent));
    if(nl->IsAtom(xObjectType) &&
       nl->SymbolValue(xObjectType) == "network")
    {
      // Get name of the network
      ListExpr xObjectName = nl->Second(xCurrent);
      string strObjectName = nl->SymbolValue(xObjectName);

      Word xValue;
      bool bDefined;
      bool bOk = SecondoSystem::GetCatalog()->GetObject(strObjectName,
                                           xValue,
                                           bDefined);
      if(bDefined && bOk)
      {
        Network* pNetwork = (Network*)xValue.addr;
        if (!found && pNetwork->GetId() == in_iNetworkId)
        {
          netList->insert(pair<int,string>(in_iNetworkId, strObjectName));
          pNetResult = (Network*) xValue.addr;
        }
        else
        {
          if (found && pNetwork->GetId() == in_iNetworkId)
          {
            netList->erase(in_iNetworkId);
            netList->insert(pair<int,string>(in_iNetworkId, strObjectName));
            pNetResult = (Network*) xValue.addr;
          }
          else
          {
            map<int,string>::iterator curIt = netList->find(pNetwork->GetId());
            if (curIt == netList->end())
              netList->insert(pair<int,string>(pNetwork->GetId(),
                                               strObjectName));
            else
            {
              if ((*curIt).second != strObjectName)
              {
                netList->erase(pNetwork->GetId());
                netList->insert(pair<int,string>(pNetwork->GetId(),
                                                strObjectName));
              }
            }
            SecondoSystem::GetCatalog()->CloseObject(nl->SymbolAtom("network"),
                                      xValue);
          }
        }
      }
    }
  }
  return pNetResult;
}

Network* NetworkManager::GetNetwork(int in_iNetworkId)
{
  // Search in all objects in the current database for a network
  ListExpr xObjectList = SecondoSystem::GetCatalog()->ListObjects();
  xObjectList = nl->Rest(xObjectList);
  while(!nl->IsEmpty(xObjectList))
  {
    // Next element in list
    ListExpr xCurrent = nl->First(xObjectList);
    xObjectList = nl->Rest(xObjectList);

    // Type of object is at fourth position in list
    ListExpr xObjectType = nl->First(nl->Fourth(xCurrent));
    if(nl->IsAtom(xObjectType) &&
       nl->SymbolValue(xObjectType) == "network")
    {
      // Get name of the network
      ListExpr xObjectName = nl->Second(xCurrent);
      string strObjectName = nl->SymbolValue(xObjectName);

      // Load object to find out the id of the network. Normally their
      // won't be to much networks in one database giving us a good
      // chance to load only the wanted network.
      Word xValue;
      bool bDefined;
      bool bOk = SecondoSystem::GetCatalog()->GetObject(strObjectName,
                                                        xValue,
                                                        bDefined);
      if(!bDefined || !bOk)
      {
        // Undefined network
        continue;
      }
      Network* pNetwork = (Network*)xValue.addr;
      if(pNetwork->GetId() == in_iNetworkId)
      {
        // This is the network we have been looking for
        return pNetwork;
      }

      SecondoSystem::GetCatalog()->CloseObject(nl->SymbolAtom("network"),
                                               xValue);
    }
  }
  return 0;
}

/*
Closes a network retrived via getNetwork.

*/
void NetworkManager::CloseNetwork(Network* in_pNetwork)
{
  Word xValue;
  xValue.addr = in_pNetwork;
  SecondoSystem::GetCatalog()->CloseObject(nl->SymbolAtom( "network" ),
                                           xValue);
}