connext::SampleRef< T > Class Template Reference

A data sample and related information received from the middleware. More...

Public Member Functions
	SampleRef ()
	Creates an object with no data.
	SampleRef (T *data, Info *info)
	Creates an object with a reference to a data object.
	SampleRef (T &data, Info &info)
	Creates an object with a reference to a data object.
	SampleRef (Sample< T > &sample)
	Copies the references to data and info.
SampleRef &	operator= (Sample< T > &sample)
	Copies the references to data and info.
T &	data () const
	Gets the data this sample contains.
Info &	info () const
	Gets the SampleInfo.
	operator T & () const
	Gets the data this sample contains.
void	set_data (T &data)
	Sets a reference to a data object.
void	set_info (DDS_SampleInfo &info)
	Sets the info object.
bool	is_nil_data () const
	Indicates if this SampleRef contains a reference to data or not.
bool	is_nil_info () const
	Indicates if this SampleRef contains a reference to data or not.
SampleIdentity_t	identity () const
	Gets the identity of this sample.
SampleIdentity_t	related_identity () const
	Gets the identity of a sample that is related to this one.

Detailed Description

template<typename T>
class connext::SampleRef< T >

A data sample and related information received from the middleware.

A SampleRef can be used much like a connext::Sample, but it's different in that it holds references to data and DDS_SampleInfo, whereas a Sample is a value type and owns its data and info.

When calling an operation that copies data from the middleware into a Sample (e.g. connext::Requester::take_reply(Sample<TRep>&)), the references to its data and information must have been set explicitly (see connext::SampleRef::set_data(T&) and connext::SampleRef::set_info(DDS_SampleInfo&))

When a SampleRef is copied, the destination SampleRef references the same data and info objects as the source. Copying and passing by value are inexpensive operations.

SampleRef is also the type of the elements in a connext::LoanedSamples container and they hold references to data from the middleware.

Template Parameters

T	The data type that this sample contains

See Also

connext::Requester::receive_reply(Sample<TRep>&, const Duration_t&)

connext::Requester::take_reply(Sample<TRep>&)

connext::Replier::receive_request(Sample<TReq>&, const Duration_t&)

Basic Requester example using SampleRef

Template Parameters

T	The data type that this sample can contain

Constructor & Destructor Documentation

template<typename T >

connext::SampleRef< T >::SampleRef ( )

inline

Creates an object with no data.

See Also

set_data(T&)

template<typename T >

connext::SampleRef< T >::SampleRef ( T *  data, Info *  info  )

inline

Creates an object with a reference to a data object.

See Also

set_data(T&)

template<typename T >

connext::SampleRef< T >::SampleRef ( T &  data, Info &  info  )

inline

Creates an object with a reference to a data object.

See Also

set_data(T&)

template<typename T >

connext::SampleRef< T >::SampleRef ( Sample< T > &  sample )

inline

Copies the references to data and info.

After this operation, this object contains a reference to the same data and info instances as the source.

Member Function Documentation

template<typename T >

SampleRef& connext::SampleRef< T >::operator= ( Sample< T > &  sample )

inline

Copies the references to data and info.

After this operation, this object contains a reference to the same data and info instances as the source.

template<typename T >

T& connext::SampleRef< T >::data ( ) const

inline

Gets the data this sample contains.

Precondition

Data must have been set before

See Also

connext::WriteSampleRef::set_data

connext::WriteSample::data()

template<typename T >

Info& connext::SampleRef< T >::info ( ) const

inline

Gets the SampleInfo.

Precondition

The info object must have been set

See Also

set_info(DDS_SampleInfo&)

connext::SampleRef::identity()

template<typename T >

connext::SampleRef< T >::operator T & ( ) const

inline

Gets the data this sample contains.

Precondition

Data must have been set before

See Also

connext::WriteSampleRef::set_data

connext::WriteSample::data()

template<typename T >

void connext::SampleRef< T >::set_data ( T &  data )

inline

Sets a reference to a data object.

Parameters

data	The data object this sample will reference

template<typename T >

void connext::SampleRef< T >::set_info ( DDS_SampleInfo &  info )

inline

Sets the info object.

template<typename T >

bool connext::SampleRef< T >::is_nil_data ( ) const

inline

Indicates if this SampleRef contains a reference to data or not.

Returns

True if this sample does not contain a reference to data.

See Also

connext::SampleRef::data

connext::SampleRef::set_data(T&)

template<typename T >

bool connext::SampleRef< T >::is_nil_info ( ) const

inline

Indicates if this SampleRef contains a reference to data or not.

Returns

True if this sample does not contain a reference to info.

See Also

connext::SampleRef::info()

connext::SampleRef::set_info(DDS_SampleInfo&)

template<typename T >

SampleIdentity_t connext::SampleRef< T >::identity ( ) const

inline

Gets the identity of this sample.

Precondition

The info object must have been set

See Also

set_info(DDS_SampleInfo&)

connext::Sample::identity()

template<typename T >

SampleIdentity_t connext::SampleRef< T >::related_identity ( ) const

inline

Gets the identity of a sample that is related to this one.

Precondition

The info object must have been set

See Also

connext::Sample::related_identity()