void mitk::BaseData::UnRegister() const
{
#ifdef MITK_WEAKPOINTER_PROBLEM_WORKAROUND_ENABLED
if(GetReferenceCount()>1)
{
Superclass::UnRegister();
if((m_Unregistering==false) && (m_SmartSourcePointer.IsNotNull()))
{
m_Unregistering=true;
// the order of the following boolean statement is important:
// this->GetSource() returns a SmartPointer,
// which increases and afterwards decreases the reference count,
// which may result in an ExternalReferenceCount of 0, causing
// BaseProcess::UnRegister() to destroy us (also we already
// about to do that).
if((this->m_SmartSourcePointer->GetExternalReferenceCount()==0) || (this->GetSource().IsNull()))
m_SmartSourcePointer=NULL; // now the reference count is zero and this object has been destroyed; thus nothing may be done after this line!!
else
m_Unregistering=false;
}
}
else
#endif
Superclass::UnRegister(); // now the reference count is zero and this object has been destroyed; thus nothing may be done after this line!!
}
void mitk::BaseProcess::UnRegister() const
{
#ifdef MITK_WEAKPOINTER_PROBLEM_WORKAROUND_ENABLED
if((m_Unregistering==false) && (m_CalculatingExternalReferenceCount==false))
{
m_Unregistering=true;
int realReferenceCount = GetExternalReferenceCount()-1; //-1 because someone is trying to unregister us
if(realReferenceCount<0)
m_ExternalReferenceCount=realReferenceCount=0;
if(realReferenceCount==0)
{
DataObjectPointerArray& outputs = const_cast<mitk::BaseProcess*>(this)->GetOutputs();
//disconnect all outputs from us
//size of outputs will not change until the very last output
//is removed, because we remove from front to back
unsigned int idx;
for (idx = 0; idx < outputs.size(); ++idx)
{
const_cast<mitk::BaseProcess*>(this)->RemoveOutput(outputs[idx]);
}
//now the referenceCount should be one!
int testReferenceCount=GetReferenceCount();
if(testReferenceCount!=1)
{
itkWarningMacro(<<"Reference count of process object unexpectedly "
<< "not 1 before final unregister but " << testReferenceCount);
}
int mitk::BaseData::GetExternalReferenceCount() const
{
if(m_CalculatingExternalReferenceCount==false) //this is only needed because a smart-pointer to m_Outputs (private!!) must be created by calling GetOutputs.
{
m_CalculatingExternalReferenceCount = true;
m_ExternalReferenceCount = -1;
int realReferenceCount = GetReferenceCount();
if(GetSource().IsNull())
{
m_ExternalReferenceCount = realReferenceCount;
m_CalculatingExternalReferenceCount = false;
return m_ExternalReferenceCount;
}
mitk::BaseProcess::DataObjectPointerArray outputs = m_SmartSourcePointer->GetOutputs();
unsigned int idx;
for (idx = 0; idx < outputs.size(); ++idx)
{
//references of outputs that are not referenced from someone else (reference additional to the reference from this BaseProcess object) are interpreted as non-existent
if(outputs[idx]==this)
--realReferenceCount;
}
m_ExternalReferenceCount = realReferenceCount;
if(m_ExternalReferenceCount<0)
m_ExternalReferenceCount=0;
m_CalculatingExternalReferenceCount = false;
}
else
return -1;
return m_ExternalReferenceCount;
}
int mitk::BaseProcess::GetExternalReferenceCount() const
{
if(m_CalculatingExternalReferenceCount==false) //this is only needed because a smart-pointer to m_Outputs (private!!) must be created by calling GetOutputs.
{
m_CalculatingExternalReferenceCount = true;
m_ExternalReferenceCount = -1;
DataObjectPointerArray& outputs = const_cast<mitk::BaseProcess*>(this)->GetOutputs();
int realReferenceCount = GetReferenceCount();
unsigned int idx;
for (idx = 0; idx < outputs.size(); ++idx)
{
//references of outputs that are not referenced from someone else (reference additional to the reference from this BaseProcess object) are interpreted as non-existent
if((outputs[idx]) && (outputs[idx]->GetReferenceCount()==1))
--realReferenceCount;
}
m_ExternalReferenceCount = realReferenceCount;
if(m_ExternalReferenceCount<0)
m_ExternalReferenceCount=0;
}
else
return -1;
m_CalculatingExternalReferenceCount = false; //do not move in if-part!!!
return m_ExternalReferenceCount;
}
