20.1.4.5. ReadCondition

class ReadCondition : public eprosima::fastdds::dds::Condition

A Condition specifically dedicated to read operations and attached to one DataReader.

ReadCondition objects allow an application to specify the data samples it is interested in (by specifying the desired sample_states, view_states, and instance_states). The condition will only be triggered when suitable information is available. They are to be used in conjunction with a WaitSet as normal conditions. More than one ReadCondition may be attached to the same DataReader.

Public Functions

virtual bool get_trigger_value() const noexcept override

Retrieves the trigger_value of the Condition.

Returns:

true if trigger_value is set to ‘true’, ‘false’ otherwise

DataReader *get_datareader() const noexcept

Retrieves the DataReader associated with the ReadCondition.

Note that there is exactly one DataReader associated with each ReadCondition.

Returns:

pointer to the DataReader associated with this ReadCondition.

SampleStateMask get_sample_state_mask() const noexcept

Retrieves the set of sample_states taken into account to determine the trigger_value of this condition.

Returns:

the sample_states specified when the ReadCondition was created.

ViewStateMask get_view_state_mask() const noexcept

Retrieves the set of view_states taken into account to determine the trigger_value of this condition.

Returns:

the view_states specified when the ReadCondition was created.

InstanceStateMask get_instance_state_mask() const noexcept

Retrieves the set of instance_states taken into account to determine the trigger_value of this condition.

Returns:

the instance_states specified when the ReadCondition was created.