Event.icc

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// Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
#ifndef XAODROOTACCESS_EVENT_ICC
#define XAODROOTACCESS_EVENT_ICC
 
// EDM include(s):
#include "AthContainers/normalizedTypeinfoName.h"
 
// System include(s).
#include <utility>
 
namespace xAOD {
 
/// This function works pretty much like StoreGateSvc::contains. It can be
/// used to check if an object with a given type having a given key can be
/// retrieved from the event.
///
/// @param key The key/name of the object
/// @returns @c true if the object is available,
///          @c false otherwise
///
template <typename T>
bool Event::contains(const std::string& key) {
 
  static const bool METADATA = false;
  const std::type_info& ti = typeid(T);
  return contains(key, ti, METADATA);
}
 
/// This function works pretty much like StoreGateSvc::transientContains.
/// It doesn't try to do any I/O operations, it just checks if an object
/// of a given type, with a given key, is already in memory.
///
/// @param key The key/name of the object
/// @returns The usual @c StatusCode types
///
template <typename T>
bool Event::transientContains(const std::string& key) const {
 
  static const bool METADATA = false;
  const std::type_info& ti = typeid(T);
  return transientContains(key, ti, METADATA);
}
 
/// This can be useful in generic client code to process all objects of a given
/// type.
///
/// @param vkeys will be filled with the list of keys (may be empty)
/// @param metadata Whether to look for metadata or data objects
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::keys(std::vector<std::string>& vkeys, bool metadata) const {
 
  ATH_CHECK(getNames(SG::normalizedTypeinfoName(typeid(T)), vkeys, metadata));
  return StatusCode::SUCCESS;
}
 
/// This function needs to be used when retrieving an object either from
/// the input or the output object list. The returned object can not be
/// modified.
///
/// @param obj The pointer that will be set to the object requested
/// @param key The key/name of the object
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::retrieve(const T*& obj, const std::string& key) {
 
  // The type in question.
  const std::type_info& ti = typeid(T);
  // Look among the output objects first.
  static const bool METADATA = false;
  const void* result = getOutputObject(key, ti, METADATA);
  // Check if it succeeded.
  if (result == nullptr) {
    // Try the input then.
    static const bool SILENT = false;
    result = getInputObject(key, ti, SILENT, METADATA);
    if (result == nullptr) {
      ATH_MSG_WARNING("Couldn't (const) retrieve \""
                      << SG::normalizedTypeinfoName(ti) << "/" << key << "\"");
      return StatusCode::RECOVERABLE;
    }
  } else {
    // Even if there is an output object with this key, it may
    // be an input object that was copied to the output. So let's
    // try to silently retrieve an input object as well. This makes
    // sure that the input/output object is updated for the current
    // event.
    static const bool SILENT = true;
    getInputObject(key, ti, SILENT, METADATA);
  }
 
  // If we were successful.
  obj = reinterpret_cast<const T*>(result);
  return StatusCode::SUCCESS;
}
 
/// This function can be used to retrieve an object from the output list.
/// Since only output objects are considered, the function returns a
/// non-const object, allowing downstream code to modify an object that
/// was put into the event somewhere upstream.
///
/// @param obj The pointer that will be set to the object requested
/// @param key The key/name of the object
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::retrieve(T*& obj, const std::string& key) {
 
  // The type in question.
  const std::type_info& ti = typeid(T);
  // Only look among the output objects in this case:
  static const bool METADATA = false;
  void* result = getOutputObject(key, ti, METADATA);
  // Check if we found the object:
  if (result == nullptr) {
    ATH_MSG_WARNING("Couldn't (non-const) retrieve \""
                    << SG::normalizedTypeinfoName(ti) << "/" << key << "\"");
    return StatusCode::RECOVERABLE;
  }
 
  // If we were successful.
  obj = reinterpret_cast<T*>(result);
  return StatusCode::SUCCESS;
}
 
/// This function can be used to add an object to the output. The function
/// takes posession of the object, so the user code must not delete an
/// object that was added to an event.
///
/// @param obj Pointer to the object to be added to the event
/// @param key The key/name to give the object
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::record(T* obj, const std::string& key) {
 
  // Just call the non-templated implementation.
  static const bool OVERWRITE = false;
  static const bool METADATA = false;
  static const bool ISOWNER = true;
  ATH_CHECK(record(obj, SG::normalizedTypeinfoName(typeid(T)), key, OVERWRITE,
                   METADATA, ISOWNER));
  return StatusCode::SUCCESS;
}
 
/// This function is used to add an object to the output. As the interface
/// clearly states, the function takes posession of the object given to it.
/// Since the user must give up ownership of the object in order to call this
/// function, it doesn't even need to be said that the user must not delete
/// the object by hand after calling this function.
///
/// @param obj Smart pointer to the object to tbe added to the event
/// @param key The key/name to give the object
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::record(std::unique_ptr<T> obj, const std::string& key) {
 
  // Just call the non-templated implementation.
  static const bool OVERWRITE = false;
  static const bool METADATA = false;
  static const bool ISOWNER = true;
  ATH_CHECK(record(obj.get(), SG::normalizedTypeinfoName(typeid(T)), key,
                   OVERWRITE, METADATA, ISOWNER));
 
  // If the record was successful, let's release the object from the unique
  // pointer.
  std::ignore = obj.release();
  return StatusCode::SUCCESS;
}
 
/// This function works pretty much like StoreGateSvc::contains for metadata
/// objects. It can be used to check if a metadata object with a given type
/// having a given key can be (const) retrieved.
///
/// @param key The key/name of the metadata object
/// @returns @c true if the object is available,
///          @c false otherwise
///
template <typename T>
bool Event::containsMeta(const std::string& key) {
 
  static const bool METADATA = true;
  static const bool SILENT = true;
  const std::type_info& ti = typeid(T);
  return ((getOutputObject(key, ti, METADATA) != nullptr) ||
          (getInputObject(key, ti, SILENT, METADATA) != nullptr));
}
 
/// This function works pretty much like StoreGateSvc::transientContains for
/// metadata objects. It doesn't try to do any I/O operations, it just checks
/// if an object of a given type, with a given key, can be retrieved in
/// non-const mode.
///
/// @param key The key/name of the metadata object
/// @returns @c true if the object is available,
///          @c false otherwise
///
template <typename T>
bool Event::transientContainsMeta(const std::string& key) const {
 
  static const bool METADATA = true;
  const std::type_info& ti = typeid(T);
  return (getOutputObject(key, ti, METADATA) != nullptr);
}
 
/// This can be useful in generic client code to process all metadata objects of
/// a given type.
///
/// @param vkeys will be filled with the list of keys (may be empty)
/// @returns The usual @c StatusCode types
///
template <typename T>
StatusCode Event::metaKeys(std::vector<std::string>& vkeys) const {
 
  static const bool METADATA = true;
  ATH_CHECK(getNames(SG::normalizedTypeinfoName(typeid(T)), vkeys, METADATA));
  return StatusCode::SUCCESS;
}
 
/// This function can be used to retrieve an object from the input metadata
/// list.
///
/// @param obj The pointer that will be set to the object requested
/// @param key The key/name of the object
/// @returns The usual @c StatusCode values
///
template <typename T>
StatusCode Event::retrieveMetaInput(const T*& obj, const std::string& key) {
 
  // Only look among the output objects in this case.
  static const bool SILENT = false;
  static const bool METADATA = true;
  const std::type_info& ti = typeid(T);
  const void* result = getInputObject(key, ti, SILENT, METADATA);
  // Check if we found the object.
  if (result == nullptr) {
    ATH_MSG_WARNING("Couldn't (const) retrieve \""
                    << SG::normalizedTypeinfoName(ti) << "/" << key << "\"");
    return StatusCode::RECOVERABLE;
  }
 
  // If we were successful.
  obj = reinterpret_cast<const T*>(result);
  return StatusCode::SUCCESS;
}
 
/// This function can be used to retrieve an object from the output metadata
/// list.
///
/// @param obj The pointer that will be set to the object requested
/// @param key The key/name of the object
/// @returns The usual @c StatusCode values
///
template <typename T>
StatusCode Event::retrieveMetaOutput(const T*& obj, const std::string& key) {
 
  // Only look among the output objects in this case:
  static const bool METADATA = true;
  const std::type_info& ti = typeid(T);
  const void* result = getOutputObject(key, ti, METADATA);
  // Check if we found the object.
  if (result == nullptr) {
    ATH_MSG_WARNING("Couldn't (const) retrieve \""
                    << SG::normalizedTypeinfoName(ti) << "/" << key << "\"");
    return StatusCode::RECOVERABLE;
  }
 
  // If we were successful.
  obj = reinterpret_cast<const T*>(result);
  return StatusCode::SUCCESS;
}
 
/// This function can be used to retrieve an object from the output metadata
/// list.
///
/// @param obj The pointer that will be set to the object requested
/// @param key The key/name of the object
/// @returns The usual @c StatusCode values
///
template <typename T>
StatusCode Event::retrieveMetaOutput(T*& obj, const std::string& key) {
 
  // Only look among the output objects in this case.
  static const bool METADATA = true;
  const std::type_info& ti = typeid(T);
  void* result = getOutputObject(key, ti, METADATA);
  // Check if we found the object.
  if (result == nullptr) {
    ATH_MSG_WARNING("Couldn't (non-const) retrieve \""
                    << SG::normalizedTypeinfoName(ti) << "/" << key << "\"");
    return StatusCode::RECOVERABLE;
  }
 
  // If we were successful.
  obj = reinterpret_cast<T*>(result);
  return StatusCode::SUCCESS;
}
 
/// This function can be used to add a metadata object to the output.
/// The function takes posession of the object, so the user code must not
/// delete an object that was added to the output.
///
/// @param obj Pointer to the object to be added to the output metadata
/// @param key The key/name to give the object
/// @returns The usual @c StatusCode values
///
template <typename T>
StatusCode Event::recordMeta(T* obj, const std::string& key) {
 
  // Just call the non-templated implementation.
  static const bool OVERWRITE = false;
  static const bool METADATA = true;
  static const bool ISOWNER = true;
  ATH_CHECK(record(obj, SG::normalizedTypeinfoName(typeid(T)), key, OVERWRITE,
                   METADATA, ISOWNER));
  return StatusCode::SUCCESS;
}
 
/// This function can be used to add a metadata object to the output. As the
/// interface clearly states, the function takes posession of the object
/// given to it. So it's not even worth mentioning that the user must not
/// delete the object after giving it to this function.
///
/// @param obj Smart pointer to the object to be added to the output metadata
/// @param key The key/name to give the object
/// @returns The usual @c StatusCode values
///
template <typename T>
StatusCode Event::recordMeta(std::unique_ptr<T> obj, const std::string& key) {
 
  // Just call the non-templated implementation.
  static const bool OVERWRITE = false;
  static const bool METADATA = true;
  static const bool ISOWNER = true;
  ATH_CHECK(record(obj.get(), SG::normalizedTypeinfoName(typeid(T)), key,
                   OVERWRITE, METADATA, ISOWNER));
 
  // If the record was successful, let's release the object from the unique
  // pointer.
  std::ignore = obj.release();
  return StatusCode::SUCCESS;
}
 
}  // namespace xAOD
 
#endif  // XAODROOTACCESS_EVENT_ICC