FWCore/Framework/src/GenericHandle.cc - master - githubmirror/cmssw

FWCore/Framework/src/GenericHandle.cc
90 строк3 KB
Andrea Bocci
Implement support for Event::getByToken for a GenericHandle
08 янв 2021, 23:35
08 янв 2021, 23:355cffea5
// -*- C++ -*-
//
// Package:     Framework
// Class  :     GenericHandle
//
// Implementation:
//     <Notes on implementation>
//
// Original Author:  Chris Jones
//         Created:  Thu Mar 30 15:48:37 EST 2006
//

// system include files

// user include files
#include "FWCore/Framework/interface/GenericHandle.h"

namespace edm {
  void convert_handle(BasicHandle&& orig, Handle<GenericObject>& result) {
    if (orig.failedToGet()) {
      result.setWhyFailedFactory(orig.whyFailedFactory());
      return;
    }
    WrapperBase const* originalWrap = orig.wrapper();
    if (originalWrap == nullptr) {
      throw Exception(errors::InvalidReference, "NullPointer") << "edm::BasicHandle has null pointer to Wrapper";
    }

    ObjectWithDict wrap(originalWrap->wrappedTypeInfo(), const_cast<WrapperBase*>(originalWrap));
    assert(bool(wrap));

    ObjectWithDict product(wrap.get("obj"));
    if (!product) {
      throw Exception(errors::LogicError) << "GenericObject could not find 'obj' member";
    }
    if (product.typeOf() != result.type()) {
      throw Exception(errors::LogicError)
          << "GenericObject asked for " << result.type().name() << " but was given a " << product.typeOf().name();
    }

    Handle<GenericObject> h(product, orig.provenance(), orig.id());
    h.swap(result);
  }

  ///Specialize the getByLabel method to work with a Handle<GenericObject>
  template <>
  bool Event::getByLabel<GenericObject>(std::string const& label,
                                        std::string const& productInstanceName,
                                        Handle<GenericObject>& result) const {
    BasicHandle bh = provRecorder_.getByLabel_(
        TypeID(result.type().typeInfo()), label, productInstanceName, std::string(), moduleCallingContext_);
    convert_handle(std::move(bh), result);  // throws on conversion error
    if (!result.failedToGet()) {
      addToGotBranchIDs(*bh.provenance());
      return true;
    }
    return false;
  }

  template <>
  bool Event::getByLabel<GenericObject>(InputTag const& tag, Handle<GenericObject>& result) const {
    if (tag.process().empty()) {
      return this->getByLabel(tag.label(), tag.instance(), result);
    } else {
      BasicHandle bh = provRecorder_.getByLabel_(
          TypeID(result.type().typeInfo()), tag.label(), tag.instance(), tag.process(), moduleCallingContext_);
      convert_handle(std::move(bh), result);  // throws on conversion error
      if (!result.failedToGet()) {
        addToGotBranchIDs(*bh.provenance());
        return true;
      }
    }
    return false;
  }

  ///Specialize the Event's getByToken method to work with a Handle<GenericObject>
  template <>
  bool Event::getByToken<GenericObject>(EDGetToken token, Handle<GenericObject>& result) const {
    result.clear();
    BasicHandle bh =
        provRecorder_.getByToken_(TypeID(result.type().typeInfo()), PRODUCT_TYPE, token, moduleCallingContext_);
    convert_handle(std::move(bh), result);  // throws on conversion error
    if (UNLIKELY(result.failedToGet())) {
      return false;
    }
    addToGotBranchIDs(*result.provenance());
    return true;
  }

}  // namespace edm