Unit GenericTosDataNode;

Interface

  Uses
    Classes,
    DataNodes;

  Type
    TTosData =
      Record
        Price : Double;
        Time : TDateTime;
        TodaysClose : Double;  // Last non-formT-Trade if not closed yet.
        Size : Integer;         // This print
        Exchange : String;
        FormT : Boolean;
        Volume : Integer;       // Total for the day.
        SaleCondition : Smallint;  // This is just for debugging.
        EventType : (etNewPrint, etMostRecentPrice); // When we first connect
                                                     // to the datafeed, we will
                                                     // get the most recent price
                                                     // and notify the listeners.
                                                     // It may happen at other
                                                     // times, such as a price
                                                     // correction.
      End;

    PTosData = ^TTosData;

    TGenericTosDataNode = Class;
    TTGenericTosDataNode = Class Of TGenericTosDataNode;

    TGenericTosDataNode =
      Class(TDataNodeWithStringKey)
      Protected
        Class Function CreateNew(Data : String) : TDataNodeWithStringKey; Override;
      Public
        Class Procedure Find(Symbol : String;
                             OnChange : TThreadMethod;
                             Out Node : TGenericTosDataNode;
                             Out Link : TDataNodeLink); Virtual;
        Function IsValid : Boolean; Virtual;
        Function GetLast : PTosData; Virtual;
        Class Procedure SetImplementation(I : TTGenericTosDataNode);
      End;

Implementation

  Var
    RealImplementation : TTGenericTosDataNode;

  Class Procedure TGenericTosDataNode.SetImplementation(I : TTGenericTosDataNode);
    Begin
      RealImplementation := I
    End;

  Class Function TGenericTosDataNode.CreateNew(Data : String) : TDataNodeWithStringKey;
    Begin
      Result := Create
    End;

  Function TGenericTosDataNode.IsValid : Boolean;
    Begin
      Result := False
    End;

  Function TGenericTosDataNode.GetLast : PTosData;
    Begin
      Result := Nil
    End;
    
  Class Procedure TGenericTosDataNode.Find(Symbol : String; OnChange : TThreadMethod; Out Node : TGenericTosDataNode; Out Link : TDataNodeLink);
    Var
      TempNode : TDataNodeWithStringKey;
    Begin
      If Assigned(RealImplementation) Then
        RealImplementation.Find(Symbol, OnChange, Node, Link)
      Else
        Begin
          FindCommon(TGenericTosDataNode, '' {Symbol}, Nil {OnChange}, TempNode, Link);
          Node := TempNode As TGenericTosDataNode
        End
    End;

End.