art::Handle< T > Class Template Reference

#include "fwd.h"

Classes
class	HandleTag

Public Types
using	element_type = T

Public Member Functions
constexpr	Handle ()=default
	Handle (GroupQueryResult const &)
T const &	operator* () const
T const *	operator-> () const
T const *	product () const
bool	isValid () const
bool	failedToGet () const
Provenance const *	provenance () const
ProductID	id () const
std::shared_ptr< art::Exception const >	whyFailed () const
void	swap (Handle< T > &other)
void	clear ()

Private Attributes
T const *	prod_ {nullptr}
Provenance	prov_ {}
std::shared_ptr< art::Exception const >	whyFailed_ {nullptr}

Detailed Description

template<typename T>
class art::Handle< T >

Definition at line 23 of file fwd.h.

Member Typedef Documentation

template<typename T>

using art::Handle< T >::element_type = T

Definition at line 101 of file Handle.h.

Constructor & Destructor Documentation

template<typename T>

constexpr art::Handle< T >::Handle ( )

explicitdefault

template<class T >

art::Handle< T >::Handle ( GroupQueryResult const &  gqr )

explicit

Definition at line 137 of file Handle.h.

References e, art::errors::LogicError, art::Handle< T >::prod_, art::Provenance::productDescription(), art::Handle< T >::prov_, and art::Handle< T >::whyFailed_.

  : prod_{nullptr}, prov_{gqr.result()}, whyFailed_{gqr.whyFailed()}
{
  if (gqr.succeeded()) {
    auto const wrapperPtr = dynamic_cast<Wrapper<T> const*>(
      gqr.result()->uniqueProduct(TypeID{typeid(Wrapper<T>)}));
    if (wrapperPtr == nullptr) {
      Exception e{errors::LogicError};
      e << "Product retrieval via Handle<T> succeeded for product:\n"
        << prov_.productDescription()
        << "but an attempt to interpret it as an object of type '"
        << cet::demangle_symbol(typeid(T).name()) << "' failed.\n";
      whyFailed_ = std::make_shared<art::Exception const>(std::move(e));
    } else {
      prod_ = wrapperPtr->product();
    }
  }
}

Member Function Documentation

template<class T >

void art::Handle< T >::clear

(

void

)

Definition at line 237 of file Handle.h.

References art::Handle< T >::swap(), and tmp.

Referenced by art::DataViewImpl::get(), art::DataViewImpl::getByLabel(), trkf::CCTrackMaker::produce(), art::DataViewImpl::removeCachedProduct(), and trkf::StitchAlg::StitchAlg().

{
  Handle<T> tmp;
  swap(tmp);
}

template<class T >

bool art::Handle< T >::failedToGet

(

)

const

Definition at line 197 of file Handle.h.

References art::Handle< T >::whyFailed_.

Referenced by cheat::RecoCheckAna::analyze(), art::DataViewImpl::get(), art::DataViewImpl::getByLabel(), art::Handle< T >::product(), evd::InfoTransfer::Rebuild(), and cheat::PhotonBackTracker::Rebuild().

{
  return whyFailed_.get();
}

template<class T >

art::ProductID art::Handle< T >::id ( ) const

inline

Definition at line 211 of file Handle.h.

References art::Provenance::isValid(), art::Provenance::productID(), and art::Handle< T >::prov_.

Referenced by art::DataViewImpl::removeCachedProduct().

{
  // FIXME: returning prov_.productID() should be sufficient since
  // ProductID{} is invalid anyway.
  return prov_.isValid() ? prov_.productID() : ProductID{};
}

template<class T >

bool art::Handle< T >::isValid

(

)

const

Definition at line 190 of file Handle.h.

References art::Provenance::isValid(), art::Handle< T >::prod_, and art::Handle< T >::prov_.

Referenced by hit::MCHitAnaExample::analyze(), MCBTDemo::analyze(), ShowerQuality::analyze(), lar_pandora::ConsolidatedPFParticleAnalysisTemplate::analyze(), shower::TCShowerAnalysis::analyze(), cluster::ClusterAna::analyze(), trkf::SpacePointAna::analyze(), trkf::SeedAna::analyze(), trkf::TrackAna::analyze(), trkf::TrackAna::anaStitch(), lar_pandora::LArPandoraHelper::BuildMCParticleHitMaps(), lar_cluster3d::StandardHit3DBuilder::CollectArtHits(), lar_pandora::LArPandoraHelper::CollectClusters(), lar_pandora::LArPandoraHelper::CollectCosmicTags(), lar_pandora::LArPandoraHelper::CollectGeneratorMCParticles(), lar_pandora::LArPandoraHelper::CollectHits(), lar_pandora::LArPandoraHelper::CollectMCParticles(), lar_pandora::LArPandoraHelper::CollectPFParticleMetadata(), lar_pandora::LArPandoraHelper::CollectPFParticles(), lar_pandora::LArPandoraHelper::CollectSeeds(), lar_pandora::LArPandoraHelper::CollectShowers(), lar_pandora::LArPandoraHelper::CollectSimChannels(), lar_pandora::LArPandoraHelper::CollectSpacePoints(), lar_pandora::LArPandoraHelper::CollectT0s(), lar_pandora::LArPandoraHelper::CollectTracks(), lar_pandora::LArPandoraHelper::CollectVertices(), lar_pandora::LArPandoraHelper::CollectWires(), t0::IndirectHitParticleAssns::CreateHitParticleAssociations(), evd::RecoBaseDrawer::DrawShower3D(), evd::RecoBaseDrawer::DrawShowerOrtho(), evd::RecoBaseDrawer::DrawTrack3D(), evd::RecoBaseDrawer::DrawTrackOrtho(), trkf::Track3DKalmanHit::getAllHits(), trkf::Track3DKalmanHit::getClusteredHits(), ShowerQuality::GetDataOrDie(), trkf::BezierTrackerModule::GetHitsFromClusters(), trkf::Track3DKalmanHit::getPFParticleStuff(), trkf::SeedFinderModule::GetSortedHitsFromClusters(), lar_cluster3d::SpacePointHit3DBuilder::Hit3DBuilder(), evgb::MCTruthAndFriendsItr::MCTruthAndFriendsItr(), MCReco::produce(), hit::MCHitFinder::produce(), cluster::SimpleClusterMerger::produce(), trkf::SpacePointCheater::produce(), trkf::SpacePointFinder::produce(), trkf::BezierTrackerModule::produce(), noisefilteralg::WireCellNoiseFilter::produce(), evwgh::EventWeight::produce(), CRHitRemoval::produce(), cluster::FuzzyClusterMerger::produce(), cosmic::TrackPFParticleMatch::produce(), ShowerReco3D::produce(), cluster::BlurredClustering::produce(), cosmic::CosmicPFParticleTagger::produce(), shower::EMShower::produce(), trkf::TrackKalmanCheater::produce(), cosmic::CosmicPCAxisTagger::produce(), t0::MCParticleTrackMatching::produce(), t0::MCParticleShowerMatching::produce(), opdet::OpHitFinder::produce(), CRHitRemovalByPCA::produce(), lbne::PhotonCounterT0Matching::produce(), t0::MCTruthT0Matching::produce(), art::DataViewImpl::removeCachedProduct(), and cluster::ClusterMergeHelper::SetClusters().

{
  return prod_ && prov_.isValid();
}

template<class T >

T const & art::Handle< T >::operator* ( ) const

inline

Definition at line 160 of file Handle.h.

References art::Handle< T >::product().

{
  return *product();
}

template<class T >

T const * art::Handle< T >::operator-> ( ) const

inline

Definition at line 180 of file Handle.h.

References art::Handle< T >::product().

{
  return product();
}

template<class T >

T const * art::Handle< T >::product

(

)

const

Definition at line 167 of file Handle.h.

References art::Handle< T >::failedToGet(), art::errors::NullPointerError, art::Handle< T >::prod_, and art::Handle< T >::whyFailed_.

Referenced by sim::DumpMCTruth::analyze(), sim::DumpGTruth::analyze(), art::Handle< T >::operator*(), art::Handle< T >::operator->(), and trkf::KalmanFilterTrajectoryFitter::produce().

{
  if (failedToGet())
    throw *whyFailed_;

  if (prod_ == nullptr)
    throw Exception(art::errors::NullPointerError)
      << "Attempt to de-reference product that points to 'nullptr'";

  return prod_;
}

template<class T >

art::Provenance const * art::Handle< T >::provenance ( ) const

inline

Definition at line 204 of file Handle.h.

References art::Handle< T >::prov_.

Referenced by ShowerQuality::analyze(), sim::DumpMCTruth::analyze(), sim::DumpGTruth::analyze(), evd::RecoBaseDrawer::DrawShower3D(), evd::RecoBaseDrawer::DrawShowerOrtho(), evd::RecoBaseDrawer::DrawTrack3D(), evd::RecoBaseDrawer::DrawTrackOrtho(), art::DataViewImpl::get(), art::DataViewImpl::getByLabel(), evgb::MCTruthAndFriendsItr::MCTruthAndFriendsItr(), lar::util::details::FindAllP< Source, Dest >::Merge(), larg4::LArG4::produce(), and art::DataViewImpl::removeCachedProduct().

{
  return &prov_;
}

template<class T>

void art::Handle< T >::swap

(

Handle< T > &

other

)

Definition at line 230 of file Handle.h.

References art::swap().

Referenced by art::Handle< T >::clear(), and art::convert_handle().

{
  std::swap(*this, other);
}

template<class T >

std::shared_ptr< art::Exception const > art::Handle< T >::whyFailed ( ) const

inline

Definition at line 220 of file Handle.h.

References art::Handle< T >::whyFailed_.

Referenced by anab::FVectorReader< T, N >::FVectorReader(), and cheat::PhotonBackTracker::Rebuild().

{
  return whyFailed_;
}

Member Data Documentation

template<typename T>

T const* art::Handle< T >::prod_ {nullptr}

private

Definition at line 128 of file Handle.h.

Referenced by art::Handle< T >::Handle(), art::Handle< T >::isValid(), and art::Handle< T >::product().

template<typename T>

Provenance art::Handle< T >::prov_ {}

private

Definition at line 129 of file Handle.h.

Referenced by art::Handle< T >::Handle(), art::Handle< T >::id(), art::Handle< T >::isValid(), and art::Handle< T >::provenance().

template<typename T>

std::shared_ptr<art::Exception const> art::Handle< T >::whyFailed_ {nullptr}

private

Definition at line 130 of file Handle.h.

Referenced by art::Handle< T >::failedToGet(), art::Handle< T >::Handle(), art::Handle< T >::product(), and art::Handle< T >::whyFailed().

---

The documentation for this class was generated from the following files:

• art/Framework/Principal/fwd.h
• art/Framework/Principal/Handle.h