include/opencascade/TObj_TReference.hxx

0001 // Created on: 2004-11-23
0002 // Created by: Pavel TELKOV
0003 // Copyright (c) 2004-2014 OPEN CASCADE SAS
0004 //
0005 // This file is part of Open CASCADE Technology software library.
0006 //
0007 // This library is free software; you can redistribute it and/or modify it under
0008 // the terms of the GNU Lesser General Public License version 2.1 as published
0009 // by the Free Software Foundation, with special exception defined in the file
0010 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
0011 // distribution for complete text of the license and disclaimer of any warranty.
0012 //
0013 // Alternatively, this file may be used under the terms of Open CASCADE
0014 // commercial license or contractual agreement.
0015
0016 // The original implementation Copyright: (C) RINA S.p.A
0017
0018 #ifndef TObj_TReference_HeaderFile
0019 #define TObj_TReference_HeaderFile
0020
0021 #include <TDF_Attribute.hxx>
0022 #include <TDF_Label.hxx>
0023
0024 class TObj_Object;
0025 class Standard_GUID;
0026
0027 /**
0028 * Attribute for storing references to the objects which implement
0029 * TObj_Object interface in the OCAF tree.
0030 * Its persistency mechanism provides transparent method for storing
0031 * cross-model references.
0032 * Each reference, when created, registers itself in the referred object,
0033 * to support back references
0034 */
0035
0036 class TObj_TReference : public TDF_Attribute
0037 {
0038  public:
0039   //! Standard methods of OCAF attribute
0040
0041   //! Empty constructor
0042   Standard_EXPORT TObj_TReference();
0043
0044   //! This method is used in implementation of ID()
0045   static Standard_EXPORT const Standard_GUID& GetID();
0046
0047   //! Returns the ID of TObj_TReference attribute.
0048   Standard_EXPORT const Standard_GUID& ID() const Standard_OVERRIDE;
0049
0050  public:
0051   //! Method for create TObj_TReference object
0052
0053   //! Creates reference on TDF_Label <theLabel> to the object <theObject> and
0054   //! creates backreference from the object <theObject> to <theMaster> one.
0055   static Standard_EXPORT Handle(TObj_TReference) Set
0056                          (const TDF_Label&               theLabel,
0057                           const Handle(TObj_Object)& theObject,
0058                           const Handle(TObj_Object)& theMaster);
0059
0060  public:
0061   //! Methods for setting and obtaining referenced object
0062
0063   //! Sets the reference to the theObject
0064   Standard_EXPORT void Set(const Handle(TObj_Object)& theObject,
0065                            const TDF_Label&               theMasterLabel);
0066
0067   //! Sets the reference to the theObject at indicated Label.
0068   //! It is method for persistent only. Don`t use anywhere else.
0069   Standard_EXPORT void Set(const TDF_Label& theLabel,
0070                            const TDF_Label& theMasterLabel);
0071
0072   //! Returns the referenced theObject
0073   Standard_EXPORT Handle(TObj_Object) Get() const;
0074
0075   //! Returns the Label of master object.
0076   TDF_Label GetMasterLabel() const {return myMasterLabel;}
0077
0078   //! Returns the referred label.
0079   TDF_Label GetLabel() const {return myLabel;}
0080
0081  public:
0082   //! Redefined OCAF abstract methods
0083
0084   //! Returns an new empty TObj_TReference attribute. It is used by the
0085   //! copy algorithm.
0086   Standard_EXPORT Handle(TDF_Attribute) NewEmpty() const Standard_OVERRIDE;
0087
0088   //! Restores the backuped contents from <theWith> into this one. It is used
0089   //! when aborting a transaction.
0090   Standard_EXPORT void Restore(const Handle(TDF_Attribute)& theWith) Standard_OVERRIDE;
0091
0092   //! This method is used when copying an attribute from a source structure
0093   //! into a target structure.
0094   Standard_EXPORT void Paste(const Handle(TDF_Attribute)&       theInto,
0095                              const Handle(TDF_RelocationTable)& theRT) const Standard_OVERRIDE;
0096
0097   //! Remove back references of it reference if it is in other document.
0098   virtual Standard_EXPORT void BeforeForget() Standard_OVERRIDE;
0099
0100   //! It is necessary for tranzaction mechanism (Undo/Redo).
0101   virtual Standard_EXPORT Standard_Boolean BeforeUndo
0102                    (const Handle(TDF_AttributeDelta)& theDelta,
0103                     const Standard_Boolean            isForced = Standard_False) Standard_OVERRIDE;
0104
0105   //! It is necessary for tranzaction mechanism (Undo/Redo).
0106   virtual Standard_EXPORT Standard_Boolean AfterUndo
0107                    (const Handle(TDF_AttributeDelta)& theDelta,
0108                     const Standard_Boolean            isForced = Standard_False) Standard_OVERRIDE;
0109
0110   //! Check if back reference exists for reference.
0111   virtual Standard_EXPORT void AfterResume() Standard_OVERRIDE;
0112
0113   //! Called after retrieval reference from file.
0114   virtual Standard_EXPORT Standard_Boolean AfterRetrieval
0115                          (const Standard_Boolean forceIt = Standard_False) Standard_OVERRIDE;
0116
0117  private:
0118   //! Fields
0119   TDF_Label myLabel;          //!< Label that indicate referenced object
0120   TDF_Label myMasterLabel;    //!< Label of object that have this reference.
0121
0122  public:
0123   //! CASCADE RTTI
0124   DEFINE_STANDARD_RTTIEXT(TObj_TReference,TDF_Attribute)
0125 };
0126
0127 //! Define handle class for TObj_TReference
0128 DEFINE_STANDARD_HANDLE(TObj_TReference,TDF_Attribute)
0129
0130 #endif
0131
0132 #ifdef _MSC_VER
0133 #pragma once
0134 #endif