dds::core::Reference< DELEGATE > Class Template Reference

The Reference class defines the abstract behavior for those type defined as "reference-type" in the DDS-PSM-CXX specification. More...

Inheritance diagram for dds::core::Reference< DELEGATE >:

Public Member Functions
	Reference (dds::core::null_type &)
	Creates a "null" reference.
	Reference (const Reference &ref)
	Creates a reference from another. More...
template<typename D >
	Reference (const Reference< D > &ref)
	Enables safe assignment from other reference types. More...
	Reference (DELEGATE_T *p)
	The following two constructors create a dds Reference from a vendor specific delegate. More...
	~Reference ()
	Destroys a reference.
template<typename R >
bool	operator== (const R &ref) const
	Compares two reference objects and returns true if they are equal. More...
template<typename R >
bool	operator!= (const R &ref) const
	Compares two reference objects and returns true if they are not-equal. More...
Reference &	operator= (const null_type)
	Special assignment operators that takes care of assigning null to this reference. More...
bool	is_nil () const
	Returns true if this reference object is nil, meaning pointing to null.
bool	operator== (const null_type) const
	Special operator== used to check if this reference object equals the null reference. More...
bool	operator!= (const null_type nil) const
	Special operator!= used to check if this reference object does not equals the null reference. More...
const DELEGATE_REF_T &	delegate () const
	Returns a reference to the underlying delegate. More...
DELEGATE_REF_T &	delegate ()
	Returns a reference to the underlying delegate. More...
DELEGATE *	operator-> ()
	The operator->() is provided to be able to directly invoke methods on the delegate. More...
const DELEGATE *	operator-> () const
	The operator->() is provided to be able to directly invoke methods on the delegate. More...

Detailed Description

template<typename DELEGATE>
class dds::core::Reference< DELEGATE >

The Reference class defines the abstract behavior for those type defined as "reference-type" in the DDS-PSM-CXX specification.

Constructor & Destructor Documentation

Reference() [1/3]

template<typename DELEGATE>

dds::core::Reference< DELEGATE >::Reference ( const Reference< DELEGATE > &  ref )

explicit

Creates a reference from another.

Parameters

ref	the other reference

Reference() [2/3]

template<typename DELEGATE>

template<typename D >

dds::core::Reference< DELEGATE >::Reference ( const Reference< D > &  ref )

explicit

Enables safe assignment from other reference types.

Parameters

ref	the other reference

Reference() [3/3]

template<typename DELEGATE>

dds::core::Reference< DELEGATE >::Reference ( DELEGATE_T *  p )

explicit

The following two constructors create a dds Reference from a vendor specific delegate.

They are public, because the implementation of other delegates may need to be able to create References in that manner.

Member Function Documentation

delegate() [1/2]

template<typename DELEGATE>

const DELEGATE_REF_T& dds::core::Reference< DELEGATE >::delegate

(

)

const

Returns a reference to the underlying delegate.

This can be used to invoke non-standard extensions provided by the DDS implementor.

Returns

a reference to delegate.

delegate() [2/2]

template<typename DELEGATE>

DELEGATE_REF_T& dds::core::Reference< DELEGATE >::delegate

(

)

Returns a reference to the underlying delegate.

This can be used to invoke non-standard extensions provided by the DDS implementor.

Returns

a reference to delegate.

operator!=() [1/2]

template<typename DELEGATE>

template<typename R >

bool dds::core::Reference< DELEGATE >::operator!=

(

const R &

ref

)

const

Compares two reference objects and returns true if they are not-equal.

Inequality is based on the referential inequality of the object being pointed.

Parameters

ref	the other reference object

operator!=() [2/2]

template<typename DELEGATE>

bool dds::core::Reference< DELEGATE >::operator!=

(

const null_type

nil

)

const

Special operator!= used to check if this reference object does not equals the null reference.

The non-null-check can be done like this: bool is_null = (r != dds::null); If r is a non-null reference the is_null variable will have the false value.

Returns

true if this reference is null.

operator->() [1/2]

template<typename DELEGATE>

DELEGATE* dds::core::Reference< DELEGATE >::operator->

(

)

The operator->() is provided to be able to directly invoke methods on the delegate.

The choice to provide direct access to the delegate was motivated by the need for providing a way that was not invasive with respect to the CXXDDS API and yet would allow for Vendor Specific extension. Thus, vendor specific extensions can be invoked on the Reference and on all its subclasses as follows:

my_dds_entity.standard_method(); my_dds_entity->vendor_specific_extension();

Returns

a reference to delegate.

operator->() [2/2]

template<typename DELEGATE>

const DELEGATE* dds::core::Reference< DELEGATE >::operator->

(

)

const

The operator->() is provided to be able to directly invoke methods on the delegate.

The choice to provide direct access to the delegate was motivated by the need for providing a way that was not invasive with respect to the CXXDDS API and yet would allow for Vendor Specific extension. Thus, vendor specific extensions can be invoked on the Reference and on all its subclasses as follows:

my_dds_entity.standard_method(); my_dds_entity->vendor_specific_extension();

Returns

a reference to delegate.

operator=()

template<typename DELEGATE>

Reference& dds::core::Reference< DELEGATE >::operator=

(

const null_type

)

Special assignment operators that takes care of assigning null to this reference.

When assigning null, there might be an associated garbage collection activity.

In essence this assignment operators takes care of allowing programmers to write: MyRefType my_ref = //... my_ref = dds::null;

operator==() [1/2]

template<typename DELEGATE>

template<typename R >

bool dds::core::Reference< DELEGATE >::operator==

(

const R &

ref

)

const

Compares two reference objects and returns true if they are equal.

Equality is based on the referential equality of the object being pointed.

Parameters

ref	the other reference object

operator==() [2/2]

template<typename DELEGATE>

bool dds::core::Reference< DELEGATE >::operator==

(

const null_type

)

const

Special operator== used to check if this reference object equals the null reference.

The null-check can be done like this: bool is_null = (r == dds::null); If r is a null reference the is_null variable will have the true value.

Returns

true if this reference is null.