dds::sub::cond::ReadCondition Class Reference

<<reference-type>> Condition specifically dedicated to read operations and attached to one dds::sub::DataReader. More...

#include <dds/sub/cond/ReadCondition.hpp>

Inheritance diagram for dds::sub::cond::ReadCondition:

Public Member Functions
template<typename T >
	ReadCondition (const dds::sub::DataReader< T > &reader, const dds::sub::status::DataState &status)
	Creates a ReadCondition. More...
template<typename T , typename Functor >
	ReadCondition (const dds::sub::DataReader< T > &reader, const dds::sub::status::DataState &status, const Functor &handler)
	Creates a ReadCondition with a handler. More...
const dds::sub::status::DataState	state_filter () const
	Returns the DataState of this condition. More...
const AnyDataReader &	data_reader () const
	Returns the DataReader associated to this condition. More...
void	close ()
	Closes the ReadCondition. More...
bool	closed () const
	Indicates whether this ReadCondition has been closed with close(). More...
Public Member Functions inherited from dds::core::cond::Condition
void	dispatch ()
	Dispatches the functors that have been registered with the condition. More...
bool	trigger_value () const
	This operation retrieves the trigger_value of the Condition. More...

Related Functions
(Note that these are not member functions.)
dds::sub::cond::detail::ReadCondition	create_read_condition_ex (const dds::sub::AnyDataReader &reader, const ::rti::sub::status::DataStateEx &status)
	<<extension>> Creates a ReadCondition with the extended DataStateEx. More...
template<typename Functor >
dds::sub::cond::detail::ReadCondition	create_read_condition_ex (const dds::sub::AnyDataReader &reader, const ::rti::sub::status::DataStateEx &status, const Functor &handler)
	<<extension>> Creates a ReadCondition with the extended DataStateEx and a handler. More...

Detailed Description

<<reference-type>> Condition specifically dedicated to read operations and attached to one dds::sub::DataReader.

dds::sub::cond::ReadCondition objects allow an application to specify the data samples it is interested in (by specifying the desired sample_states, view_states as well as instance_states in dds::sub::DataReader::read and dds::sub::DataReader::take variants.

This allows RTI Connext to enable the condition only when suitable information is available. They are to be used in conjunction with a WaitSet as normal conditions.

More than one dds::sub::cond::ReadCondition may be attached to the same dds::sub::DataReader.

Examples

Foo_subscriber.cxx.

Constructor & Destructor Documentation

ReadCondition() [1/2]

template<typename T >

dds::sub::cond::ReadCondition::ReadCondition ( const dds::sub::DataReader< T > &  reader, const dds::sub::status::DataState &  status  )

inline

Creates a ReadCondition.

Template Parameters

T	The topic-type of the DataReader.

Parameters

reader	The reader associated to the condition. One reader can have multiple ReadConditions but one ReadCondition belongs to exactly one DataReader.
status	The sample, view and instance states of interest.

See also

rti::sub::cond::create_read_condition_ex

ReadCondition() [2/2]

template<typename T , typename Functor >

dds::sub::cond::ReadCondition::ReadCondition ( const dds::sub::DataReader< T > &  reader, const dds::sub::status::DataState &  status, const Functor &  handler  )

inline

Creates a ReadCondition with a handler.

Template Parameters

T	The topic-type of the DataReader.
Functor	Any type whose instances can be called with a no-argument function call (i.e. f(), if f is an instance of Functor), or with a Condition argument (f(condition)) Examples are functions, types that override operator(), and lambdas.

Parameters

reader	The reader associated to the condition. One reader can have multiple ReadConditions but one ReadCondition belongs to exactly one DataReader.
status	The sample, view and instance states of interest.
handler	The handler that dds::core::cond::WaitSet::dispatch() will call when the condition is triggered. This argument is copied.

The following examples creates two ReadConditions with handlers. The first one receives a lambda function with no arguments. The second one receives a function with the condition as an argument.

// Example 1: lambda function with no arguments
dds::sub::cond::ReadCondition my_read_condition(
       reader,
       dds::sub::status::DataState::any(),
       []()
       {
           std::cout << "condition has been triggered\n";
       }
);
 
// Example 2: function with a condition argument
void function_handler(dds::core::cond::Condition c)
{
    // function receiving the condition
    std::cout << "condition has been triggered\n";
}
 
dds::sub::cond::ReadCondition my_read_condition2(
       reader,
       dds::sub::status::DataState::any(),
       function_handler
);

See also

dds::core::cond::WaitSet::dispatch()

WaitSet wait and dispatch examples

Member Function Documentation

state_filter()

const dds::sub::status::DataState dds::sub::cond::ReadCondition::state_filter ( ) const

inline

Returns the DataState of this condition.

data_reader()

const AnyDataReader & dds::sub::cond::ReadCondition::data_reader ( ) const

inline

Returns the DataReader associated to this condition.

To obtain the actual typed DataReader, see AnyDataReader::get()

close()

void dds::sub::cond::ReadCondition::close ( )

inline

Closes the ReadCondition.

This is a explicit deletion, which otherwise would occur when all references to this ReadCondition go out of scope.

Precondition

The ReadCondition must not be attached to any Waitsets.

Exceptions

dds::core::PreconditionNotMetError

If the ReadCondition is attached to a Waitset when it is closed.

closed()

bool dds::sub::cond::ReadCondition::closed ( ) const

inline

Indicates whether this ReadCondition has been closed with close().

Friends And Related Function Documentation

create_read_condition_ex() [1/2]

dds::sub::cond::detail::ReadCondition create_read_condition_ex ( const dds::sub::AnyDataReader &  reader, const ::rti::sub::status::DataStateEx &  status  )

related

<<extension>> Creates a ReadCondition with the extended DataStateEx.

Note

This is a standalone function in the namespace rti::sub::cond

The usual way to create a dds::sub::cond::ReadCondition is the constructor that receives a dds::sub::status::DataState. This extension function allows using rti::sub::status::DataStateEx, which includes additional state masks.

References dds::sub::condition().

create_read_condition_ex() [2/2]

template<typename Functor >

dds::sub::cond::detail::ReadCondition create_read_condition_ex ( const dds::sub::AnyDataReader &  reader, const ::rti::sub::status::DataStateEx &  status, const Functor &  handler  )

related

<<extension>> Creates a ReadCondition with the extended DataStateEx and a handler.

Note

This is a standalone function in the namespace rti::sub::cond

The usual way to create a dds::sub::cond::ReadCondition is the constructor that receives a dds::sub::status::DataState. This extension function allows using rti::sub::status::DataStateEx, which includes additional state masks.

References dds::sub::condition().