Collection::Collection ( HgcalTupleTree & d, size_t size ):
  m_data ( & d ),
  m_hlt_filter_index ( -1 )
{
  SetLeadNConstituents ( size ) ;
} 
Collection::Collection ( rootNtupleClass & d, size_t size ):
  m_data ( & d ),
  m_trigObj_index ( -1 )
{
  SetLeadNConstituents ( size ) ;
}