Initial revision

include/RefCount.hh

+/*=========================================================================
+
+  Program:   Visualization Library
+  Module:    RefCount.hh
+  Language:  C++
+  Date:      $Date$
+  Version:   $Revision$
+
+This file is part of the Visualization Library. No part of this file or its 
+contents may be copied, reproduced or altered in any way without the express
+written consent of the authors.
+
+Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen 1993, 1994 
+
+=========================================================================*/
+// .NAME vlRefCount - subclasses of this object are reference counted
+// .SECTION Description
+// vlRefCount is the base class for objects that are reference counted. 
+// Objects that are reference counted exist as long as another object
+// uses them. Once the last reference to a reference counted object is 
+// removed, the object will spontaneously destruct. Typically only data
+// objects that are passed between objects are reference counted.
+
+#ifndef __vlRefCount_hh
+#define __vlRefCount_hh
+
+#include "Object.hh"
+
+class vlRefCount : public vlObject
+{
+public:
+  vlRefCount();
+  ~vlRefCount();
+  void PrintSelf(ostream& os, vlIndent indent);
+  char *GetClassName() {return "vlRefCount";};
+
+  void Register(vlObject* o);
+  void UnRegister(vlObject* o);
+  int  GetRefCount() {return this->RefCount;};
+
+private:
+  int RefCount;      // Number of uses of this object by other objects
+};
+
+#endif
+

src/RefCount.cc

+/*=========================================================================
+
+  Program:   Visualization Library
+  Module:    RefCount.cc
+  Language:  C++
+  Date:      $Date$
+  Version:   $Revision$
+
+This file is part of the Visualization Library. No part of this file
+or its contents may be copied, reproduced or altered in any way
+without the express written consent of the authors.
+
+Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen 1993, 1994 
+
+=========================================================================*/
+#include "RefCount.hh"
+
+// Description:
+// Construct with initial reference count = 0.
+vlRefCount::vlRefCount()
+{
+  this->RefCount = 0;
+}
+
+vlRefCount::~vlRefCount() 
+{
+  if (this->RefCount > 0)
+    {
+    vlErrorMacro(<< "Trying to delete object with non-zero reference count");
+    }
+}
+
+// Description:
+// Increase the reference count (mark as used by another object).
+void vlRefCount::Register(vlObject* o)
+{
+  this->RefCount++;
+  vlDebugMacro(<< "Registered by " << o->GetClassName() << " (" << o << ")");
+}
+
+// Description:
+// Decrease the reference count (release by another object).
+void vlRefCount::UnRegister(vlObject* o)
+{
+  vlDebugMacro(<< "UnRegistered by " << o->GetClassName() << " (" << 0 << ")");
+
+  if (--this->RefCount <= 0) delete this;
+}
+
+void vlRefCount::PrintSelf(ostream& os, vlIndent indent)
+{
+  if (this->ShouldIPrint(vlRefCount::GetClassName()))
+    {
+    vlObject::PrintSelf(os,indent);
+
+    os << indent << "Reference Count: " << this->RefCount << "\n";
+    }
+}