DataHandle< DATA > Class Template Reference

an iterator over instances of a given type in StoreGateSvc. More...

#include <DataHandle.h>

Inheritance diagram for DataHandle< DATA >:

Collaboration diagram for DataHandle< DATA >:

Public Types
using	iterator_category = std::forward_iterator_tag
using	value_type = DATA
using	difference_type = std::ptrdiff_t
using	pointer = value_type*
using	reference = value_type&
typedef pointer	pointer_type
using	const_pointer_type = const DATA*
using	reference_type = reference
using	const_reference_type = const DATA&
typedef DataHandleBase::ID_type	ID_type

Public Member Functions
virtual void	finalReset ()
	optional special action on final reset call (e.g. in caller destructor)
constructors and assignment
	DataHandle ()
	DataHandle (const DataHandle &h)
DataHandle &	operator= (const DataHandle &h)
DataHandle &	operator= (const DATA &d)
virtual	~DataHandle ()
	unbind from the proxy before we go
validity checks
bool	isValid () const
	RETRIEVES the DO to check it is valid and unlocked.
bool	operator! () const
	DEPRECATED for statements like: if (!DataHandle<XXX>) {...}.
	operator int () const
	DEPRECATED for statements like: if (DataHandle<XXX>) {...}.
iterator interface
const DataHandle &	operator++ () const
	prefix
DataHandle	operator++ (int) const
	postfix
const_pointer_type	operator-> () const
const_reference_type	operator* () const
access to the underlying ptr
	operator const_pointer_type () const
	often ambiguous
const_pointer_type	cptr () const
	safer explicit ptr accessor
virtual void	reset (bool) override
	reset pointer

other constructors and methods for SG internal use
const_pointer_type	m_ptr
	DataHandle (SG::DataProxy *proxy)
	DataHandle (const SG::ConstProxyIterator &itr1, const SG::ConstProxyIterator &itr2)
virtual CLID	clid () const override
	the CLID of the object we are bound to
bool	operator==ATLAS_NOT_THREAD_SAFE (const DataHandle< DATA > &h1, const DataHandle< DATA > &h2)
bool	operator!=ATLAS_NOT_THREAD_SAFE (const DataHandle< DATA > &h1, const DataHandle< DATA > &h2)
const_pointer_type	dataPointer () const

validity checks
bool	isConst () const
bool	isInitialized () const
	weaker test but it does not touch the disk!
virtual bool	isSet () const override
virtual const std::string &	key () const override
	Get the key string with which the current object was stored.
StatusCode	setState (SG::DataProxy *proxy) const
StatusCode	setState (IProxyDict *store, const ID_type &name) const
StatusCode	setState (SG::ConstProxyIterator &itr1, const SG::ConstProxyIterator &itr2) const
StatusCode	setState (SG::DataProxy *proxy)
StatusCode	setState (IProxyDict *store, const ID_type &name)
ID_type	ID () const
	get the data object key (ID)
SG::ConstProxyIterator	m_itr
	iterator pointing at the beginning of the range of proxies
SG::ConstProxyIterator	m_itrEnd
	iterator pointing at the end of the range of proxies
SG::DataProxy *	m_proxy
	the proxy holding the object we are bound to
bool	m_useItr
	use the proxy-iterator or just the proxy ?

Detailed Description

template<typename DATA>
class DataHandle< DATA >

an iterator over instances of a given type in StoreGateSvc.

It d-casts and caches locally the pointed-at object, to speed-up subsequent accesses. It can be reset by the store for asynchronous updates (IOVSvc)

Holds a reference count on the proxy to which it's currently pointing. Note: one may think that we should hold reference counts for the entire range which the DataHandle references (if it is a range). The problem with this is that the range may change underneath us. For example, if someone does a SG record, then a new element may appear within the range. So we only hold the refcount for the object to which we're currently pointing.

Parameters

DATA	the data object type

Author

ATLAS Collaboration

Definition at line 41 of file DataHandle.h.

Member Typedef Documentation

const_pointer_type

template<typename DATA>

using DataHandle< DATA >::const_pointer_type = const DATA*

Definition at line 52 of file DataHandle.h.

const_reference_type

template<typename DATA>

using DataHandle< DATA >::const_reference_type = const DATA&

Definition at line 54 of file DataHandle.h.

difference_type

template<typename DATA>

using DataHandle< DATA >::difference_type = std::ptrdiff_t

Definition at line 47 of file DataHandle.h.

ID_type

template<typename DATA>

typedef DataHandleBase::ID_type DataHandle< DATA >::ID_type

Definition at line 56 of file DataHandle.h.

iterator_category

template<typename DATA>

using DataHandle< DATA >::iterator_category = std::forward_iterator_tag

Definition at line 45 of file DataHandle.h.

pointer

template<typename DATA>

using DataHandle< DATA >::pointer = value_type*

Definition at line 48 of file DataHandle.h.

pointer_type

template<typename DATA>

typedef pointer DataHandle< DATA >::pointer_type

Definition at line 51 of file DataHandle.h.

reference

template<typename DATA>

using DataHandle< DATA >::reference = value_type&

Definition at line 49 of file DataHandle.h.

reference_type

template<typename DATA>

using DataHandle< DATA >::reference_type = reference

Definition at line 53 of file DataHandle.h.

value_type

template<typename DATA>

using DataHandle< DATA >::value_type = DATA

Definition at line 46 of file DataHandle.h.

Constructor & Destructor Documentation

DataHandle() [1/4]

template<typename DATA>

DataHandle< DATA >::DataHandle

(

)

DataHandle() [2/4]

template<typename DATA>

DataHandle< DATA >::DataHandle

(

const DataHandle< DATA > &

h

)

~DataHandle()

template<typename DATA>

virtual DataHandle< DATA >::~DataHandle ( )

virtual

unbind from the proxy before we go

DataHandle() [3/4]

template<typename DATA>

DataHandle< DATA >::DataHandle

(

SG::DataProxy *

proxy

)

DataHandle() [4/4]

template<typename DATA>

DataHandle< DATA >::DataHandle	(	const SG::ConstProxyIterator &	itr1,
		const SG::ConstProxyIterator &	itr2 )

Member Function Documentation

clid()

template<typename DATA>

virtual CLID DataHandle< DATA >::clid ( ) const

inlineoverridevirtual

the CLID of the object we are bound to

Implements DataHandleBase.

Definition at line 120 of file DataHandle.h.

{ return ClassID_traits<DATA>::ID(); }

cptr()

template<typename DATA>

const_pointer_type DataHandle< DATA >::cptr

(

)

const

safer explicit ptr accessor

dataPointer()

template<typename DATA>

const_pointer_type DataHandle< DATA >::dataPointer ( ) const

private

finalReset()

virtual void IResetable::finalReset ( )

inlinevirtualinherited

optional special action on final reset call (e.g. in caller destructor)

Reimplemented in SG::VarHandleBase.

Definition at line 33 of file IResetable.h.

{};

ID()

ID_type DataHandleBase::ID ( ) const

inlineinherited

get the data object key (ID)

Definition at line 94 of file DataHandleBase.h.

{ return isInitialized() ? m_proxy->name() : "NONE"; }

isConst()

bool DataHandleBase::isConst ( ) const

inherited

Definition at line 196 of file DataHandleBase.cxx.

{
  return 0 != m_proxy 
    ? m_proxy->isConst() 
    : false;
}

isInitialized()

bool DataHandleBase::isInitialized ( ) const

inherited

weaker test but it does not touch the disk!

Definition at line 207 of file DataHandleBase.cxx.

{
  return (0 != m_proxy);
}

isSet()

virtual bool DataHandleBase::isSet ( ) const

inlineoverridevirtualinherited

Implements IResetable.

Definition at line 77 of file DataHandleBase.h.

{ return isInitialized(); }

isValid()

template<typename DATA>

bool DataHandle< DATA >::isValid

(

)

const

RETRIEVES the DO to check it is valid and unlocked.

key()

const std::string & DataHandleBase::key ( ) const

overridevirtualinherited

Get the key string with which the current object was stored.

Implements IResetable.

Definition at line 186 of file DataHandleBase.cxx.

{
  if (m_itr == m_itrEnd) {
    return m_proxy->name();
  } else {
    return m_itr->first;
  }
}

operator const_pointer_type()

template<typename DATA>

DataHandle< DATA >::operator const_pointer_type ( ) const

inline

often ambiguous

Definition at line 104 of file DataHandle.h.

operator int()

template<typename DATA>

DataHandle< DATA >::operator int ( ) const

inline

DEPRECATED for statements like: if (DataHandle<XXX>) {...}.

Definition at line 89 of file DataHandle.h.

{ return isValid(); }

operator!()

template<typename DATA>

bool DataHandle< DATA >::operator! ( ) const

inline

DEPRECATED for statements like: if (!DataHandle<XXX>) {...}.

Definition at line 85 of file DataHandle.h.

{ return !isValid(); }

operator*()

template<typename DATA>

const_reference_type DataHandle< DATA >::operator* ( ) const

inline

Definition at line 99 of file DataHandle.h.

{ return *cptr(); }   

operator++() [1/2]

template<typename DATA>

const DataHandle & DataHandle< DATA >::operator++

(

)

const

prefix

operator++() [2/2]

template<typename DATA>

DataHandle DataHandle< DATA >::operator++

(

int

)

const

postfix

operator->()

template<typename DATA>

const_pointer_type DataHandle< DATA >::operator-> ( ) const

inline

Definition at line 97 of file DataHandle.h.

{ return cptr(); }

operator=() [1/2]

template<typename DATA>

DataHandle & DataHandle< DATA >::operator= ( const DATA & d )

inline

Definition at line 63 of file DataHandle.h.

  { 
    typename DataHandle<DATA>::pointer_type ptr = m_ptr;
    if (ptr) {
      *ptr = d; 
    } else {
      std::cerr << "invalid proxy\n";
    }
    return *this; 
  }

operator=() [2/2]

template<typename DATA>

DataHandle & DataHandle< DATA >::operator=

(

const DataHandle< DATA > &

h

)

reset()

template<typename DATA>

virtual void DataHandle< DATA >::reset ( bool )

inlineoverridevirtual

reset pointer

Implements IResetable.

Definition at line 108 of file DataHandle.h.

setState() [1/5]

StatusCode DataHandleBase::setState ( IProxyDict * store, const ID_type & name )

inherited

Definition at line 235 of file DataHandleBase.cxx.

{
  if (0 == store) {
    return StatusCode::FAILURE;
  }
  CLID cid = this->clid();
  SG::DataProxy* proxy = store->proxy(cid, key);
  return this->setState(proxy);
}

setState() [2/5]

StatusCode DataHandleBase::setState ( IProxyDict * store, const ID_type & name ) const

inherited

Definition at line 175 of file DataHandleBase.cxx.

{
  if (0 == store) {
    return StatusCode::FAILURE;
  }
  CLID cid = this->clid();
  SG::DataProxy* proxy = store->proxy(cid, key);
  return this->setState(proxy);
}

setState() [3/5]

StatusCode DataHandleBase::setState ( SG::ConstProxyIterator & itr1, const SG::ConstProxyIterator & itr2 ) const

inherited

Definition at line 123 of file DataHandleBase.cxx.

{
  if (m_proxy) m_proxy->release();
 
  m_itr = itr;
  m_itrEnd = itrEnd;
  m_useItr = true;
 
  // ouch! FIXME ?
  // we could have a void* m_ptr data member and have a
  // typeless_dataPointer method using the typeless machinery of
  // DataProxy+DataBucketBase...
  const_cast<DataHandleBase*>(this)->reset (false);
 
  // scan from itr to itrEnd and set m_itr to the first valid iterator:
 
  for (; itr != itrEnd; ++itr) {
    if (itr->second->isValid()) {
      m_itr = itr;
      m_proxy = m_itr->second;
      if (m_proxy) m_proxy->addRef();
      return StatusCode::SUCCESS;
    }
  }
 
  m_itr = itrEnd;
  m_proxy = 0;
  
  return StatusCode::FAILURE; 
}

setState() [4/5]

StatusCode DataHandleBase::setState ( SG::DataProxy * proxy )

inherited

Definition at line 217 of file DataHandleBase.cxx.

{
  if (0 == proxy || !proxy->isValid() || proxy->isConst()) {
    return StatusCode::FAILURE;
  }
 
  if (m_proxy != proxy) {
    if (m_proxy) m_proxy->release();
    m_proxy = proxy;
    m_proxy->addRef();
  }
 
  m_useItr = false;
  this->reset (false);
  return StatusCode::SUCCESS;
}

setState() [5/5]

StatusCode DataHandleBase::setState ( SG::DataProxy * proxy ) const

inherited

Definition at line 156 of file DataHandleBase.cxx.

{
  if (0 == proxy || !proxy->isValid()) {
    return StatusCode::FAILURE;
  }
 
  if (m_proxy != proxy) {
    if (m_proxy) m_proxy->release();
    m_proxy = proxy;
    m_proxy->addRef();
  }
 
  m_useItr = false;
  const_cast<DataHandleBase*>(this)->reset (false);
 
  return StatusCode::SUCCESS;
}

Friends And Related Symbol Documentation

operator!=ATLAS_NOT_THREAD_SAFE

template<typename DATA>

bool operator!=ATLAS_NOT_THREAD_SAFE ( const DataHandle< DATA > & h1, const DataHandle< DATA > & h2 )

friend

Definition at line 130 of file DataHandle.h.

  {
    return h1.m_proxy != h2.m_proxy;
  }

operator==ATLAS_NOT_THREAD_SAFE

template<typename DATA>

bool operator==ATLAS_NOT_THREAD_SAFE ( const DataHandle< DATA > & h1, const DataHandle< DATA > & h2 )

friend

Definition at line 123 of file DataHandle.h.

  {
    return h1.m_proxy == h2.m_proxy;
  }

Member Data Documentation

m_itr

SG::ConstProxyIterator DataHandleBase::m_itr

mutableprotectedinherited

iterator pointing at the beginning of the range of proxies

Definition at line 109 of file DataHandleBase.h.

m_itrEnd

SG::ConstProxyIterator DataHandleBase::m_itrEnd

mutableprotectedinherited

iterator pointing at the end of the range of proxies

Definition at line 112 of file DataHandleBase.h.

m_proxy

SG::DataProxy* DataHandleBase::m_proxy

mutableprotectedinherited

the proxy holding the object we are bound to

Definition at line 115 of file DataHandleBase.h.

m_ptr

template<typename DATA>

const_pointer_type DataHandle< DATA >::m_ptr

mutableprivate

Definition at line 140 of file DataHandle.h.

m_useItr

bool DataHandleBase::m_useItr

mutableprotectedinherited

use the proxy-iterator or just the proxy ?

Definition at line 118 of file DataHandleBase.h.

---

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

• DataHandle.h