示例#1
0
 /// <summary>
 /// Used to commit meta model : classes This is useful when running in client
 /// server mode TODO Check this
 /// </summary>
 protected virtual void CommitMetaModel()
 {
     NeoDatis.Odb.Core.Layers.Layer2.Meta.MetaModel sessionMetaModel = session.GetMetaModel
                                                                           ();
     // If meta model has not been modified, there is nothing to do
     if (!sessionMetaModel.HasChanged())
     {
         return;
     }
     if (NeoDatis.Odb.OdbConfiguration.IsDebugEnabled(LogId))
     {
         NeoDatis.Tool.DLogger.Debug("Start commitMetaModel");
     }
     NeoDatis.Odb.Core.Layers.Layer2.Meta.MetaModel lastCommitedMetaModel = new NeoDatis.Odb.Core.Layers.Layer2.Meta.SessionMetaModel
                                                                                ();
     if (isLocal)
     {
         // In local mode, we must not reload the meta model as there is no
         // concurrent access
         lastCommitedMetaModel = sessionMetaModel;
     }
     else
     {
         // In ClientServer mode, re-read the meta-model from the database
         // base to get last update.
         lastCommitedMetaModel = session.GetStorageEngine().GetObjectReader().ReadMetaModel
                                     (lastCommitedMetaModel, false);
     }
     // Gets the classes that have changed (that have modified ,deleted or
     // inserted objects)
     System.Collections.Generic.IEnumerator <NeoDatis.Odb.Core.Layers.Layer2.Meta.ClassInfo
                                             >      cis             = sessionMetaModel.GetChangedClassInfo().GetEnumerator();
     NeoDatis.Odb.Core.Layers.Layer2.Meta.ClassInfo newCi           = null;
     NeoDatis.Odb.Core.Layers.Layer2.Meta.ClassInfo lastCommittedCI = null;
     NeoDatis.Odb.Core.Layers.Layer3.IObjectWriter  writer          = session.GetStorageEngine()
                                                                      .GetObjectWriter();
     NeoDatis.Odb.OID lastCommittedObjectOIDOfThisTransaction = null;
     NeoDatis.Odb.OID lastCommittedObjectOIDOfPrevTransaction = null;
     // for all changes between old and new meta model
     while (cis.MoveNext())
     {
         newCi = cis.Current;
         if (lastCommitedMetaModel.ExistClass(newCi.GetFullClassName()))
         {
             // The last CI represents the last committed meta model of the
             // database
             lastCommittedCI = lastCommitedMetaModel.GetClassInfoFromId(newCi.GetId());
             // Just be careful to keep track of current CI committed zone
             // deleted objects
             lastCommittedCI.GetCommitedZoneInfo().SetNbDeletedObjects(newCi.GetCommitedZoneInfo
                                                                           ().GetNbDeletedObjects());
         }
         else
         {
             lastCommittedCI = newCi;
         }
         lastCommittedObjectOIDOfThisTransaction = newCi.GetCommitedZoneInfo().last;
         lastCommittedObjectOIDOfPrevTransaction = lastCommittedCI.GetCommitedZoneInfo().last;
         NeoDatis.Odb.OID lastCommittedObjectOID = lastCommittedObjectOIDOfPrevTransaction;
         // If some object have been created then
         if (lastCommittedObjectOIDOfPrevTransaction != null)
         {
             // Checks if last object of committed meta model has not been
             // deleted
             if (session.GetCache().IsDeleted(lastCommittedObjectOIDOfPrevTransaction))
             {
                 // TODO This is wrong: if a committed transaction deleted a
                 // committed object and creates x new
                 // objects, then all these new objects will be lost:
                 // if it has been deleted then use the last object of the
                 // session class info
                 lastCommittedObjectOID = lastCommittedObjectOIDOfThisTransaction;
                 newCi.GetCommitedZoneInfo().last = lastCommittedObjectOID;
             }
         }
         // Connect Unconnected zone to connected zone
         // make next oid of last committed object point to first
         // uncommitted object
         // make previous oid of first uncommitted object point to
         // last committed object
         if (lastCommittedObjectOID != null && newCi.GetUncommittedZoneInfo().HasObjects())
         {
             if (newCi.GetCommitedZoneInfo().HasObjects())
             {
                 // these 2 updates are executed directly without
                 // transaction, because
                 // We are in the commit process.
                 writer.UpdateNextObjectFieldOfObjectInfo(lastCommittedObjectOID, newCi.GetUncommittedZoneInfo
                                                              ().first, false);
                 writer.UpdatePreviousObjectFieldOfObjectInfo(newCi.GetUncommittedZoneInfo().first
                                                              , lastCommittedObjectOID, false);
             }
             else
             {
                 // Committed zone has 0 object
                 writer.UpdatePreviousObjectFieldOfObjectInfo(newCi.GetUncommittedZoneInfo().first
                                                              , null, false);
             }
         }
         // The number of committed objects must be updated with the number
         // of the last committed CI because a transaction may have been
         // committed changing this number.
         // Notice that the setNbObjects receive the full CommittedCIZoneInfo
         // object
         // because it will set the number of objects and the number of
         // deleted objects
         newCi.GetCommitedZoneInfo().SetNbObjects(lastCommittedCI.GetCommitedZoneInfo());
         // and don't forget to set the deleted objects
         // This sets the number of objects, the first object OID and the
         // last object OID
         newCi = BuildClassInfoForCommit(newCi);
         writer.UpdateInstanceFieldsOfClassInfo(newCi, false);
         if (NeoDatis.Odb.OdbConfiguration.IsDebugEnabled(LogId))
         {
             NeoDatis.Tool.DLogger.Debug("Analysing class " + newCi.GetFullClassName());
             NeoDatis.Tool.DLogger.Debug("\t-Commited CI   = " + newCi);
             NeoDatis.Tool.DLogger.Debug("\t-connect last commited object with oid " + lastCommittedObjectOID
                                         + " to first uncommited object " + newCi.GetUncommittedZoneInfo().first);
             NeoDatis.Tool.DLogger.Debug("\t-Commiting new Number of objects = " + newCi.GetNumberOfObjects
                                             ());
         }
     }
     sessionMetaModel.ResetChangedClasses();
     // To guarantee integrity after commit, the meta model is set to null
     // If the user continues using odb instance after commit the meta model
     // will be lazy-reloaded. Only for Client Server mode
     if (!isLocal)
     {
         session.SetMetaModel(null);
     }
 }