SG::AuxElement::Accessor< T > Class Template Reference

Helper class to provide type-safe access to aux data. More...

#include <AuxElement.h>

Inheritance diagram for SG::AuxElement::Accessor< T >:

List of all members.

Public Types
typedef AuxDataTraits< T > ::reference_type	reference_type
	Type referencing an item.
typedef AuxDataTraits< T > ::element_type	element_type
	Type the user sees.
typedef AuxDataTraits< T > ::container_pointer_type	container_pointer_type
	Pointer into the container holding this item.
Public Member Functions
	Accessor (const std::string &name)
	Constructor.
	Accessor (const std::string &name, const std::string &clsname)
	Constructor.
reference_type	operator() (AuxElement &e) const
	Fetch the variable for one element, as a non-const reference.
reference_type	operator() (AuxVectorData &container, size_t index) const
	Fetch the variable for one element, as a non-const reference.
void	set (AuxElement &e, const element_type &x) const
	Set the variable for one element.
container_pointer_type	getDataArray (AuxVectorData &container) const
	Get a pointer to the start of the auxiliary data array.
bool	isAvailableWritable (const AuxElement &e) const
	Test to see if this variable exists in the store and is writable.

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Detailed Description

template<class T>
class SG::AuxElement::Accessor< T >

Helper class to provide type-safe access to aux data.

This is written as a separate class in order to be able to cache the name -> auxid lookup.

You might use this something like this:

   // Only need to do this once.
   Myclass::Accessor<int> vint1 ("myInt");
   ...
   const Myclass* m = ...;
   int x = vint1 (*m);

You can also use this to define getters/setters in your class:

  class Myclass {
    ...
    int get_x() const
    { static Accessor<int> acc ("x", "Myclass");
      return acc (*this); }
    int& get_x()
    { static Accessor<int> acc ("x", "Myclass");
      return acc (*this); }

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Constructor & Destructor Documentation

template<class T >

SG::AuxElement::Accessor< T >::Accessor

(

const std::string &

name

)

[inline]

Constructor.

Parameters:

name

Name of this aux variable.

The name -> auxid lookup is done here.

template<class T >

SG::AuxElement::Accessor< T >::Accessor	(	const std::string &	name,
		const std::string &	clsname
	)			[inline]

Constructor.

Parameters:

	name	Name of this aux variable.
	clsname	The name of its associated class. May be blank.

The name -> auxid lookup is done here.

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Member Function Documentation

template<class T >

AuxElement::Accessor< T >::container_pointer_type SG::AuxElement::Accessor< T >::getDataArray

(

AuxVectorData &

container

)

const [inline]

Get a pointer to the start of the auxiliary data array.

Parameters:

container

The container from which to fetch the variable.

template<class T >

bool SG::AuxElement::Accessor< T >::isAvailableWritable

(

const AuxElement &

e

)

const [inline]

Test to see if this variable exists in the store and is writable.

Parameters:

e

An element of the container which to test the variable.

template<class T >

AuxElement::Accessor< T >::reference_type SG::AuxElement::Accessor< T >::operator()	(	AuxVectorData &	container,
		size_t	index
	)			const [inline]

Fetch the variable for one element, as a non-const reference.

Parameters:

	container	The container from which to fetch the variable.
	index	The index of the desired element.

This allows retrieving aux data by container / index. Looping over the index via this method will be faster then looping over the elements of the container.

template<class T >

AuxElement::Accessor< T >::reference_type SG::AuxElement::Accessor< T >::operator()

(

AuxElement &

e

)

const [inline]

Fetch the variable for one element, as a non-const reference.

Parameters:

e

The element for which to fetch the variable.

template<class T >

void SG::AuxElement::Accessor< T >::set	(	AuxElement &	e,
		const element_type &	x
	)			const [inline]

Set the variable for one element.

Parameters:

	e	The element for which to fetch the variable.
	x	The variable value to set.

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

• /cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.30/AthContainers/AthContainers/AuxElement.h
• /cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.30/AthContainers/AthContainers/AuxElement.icc