dds::topic::TopicListener< T > Class Template Reference

Topic events Listener. More...

#include "Topic.hpp"

Inherited by dds::topic::NoOpTopicListener< T > [virtual].

Public Member Functions
virtual void	on_inconsistent_topic (Topic< T > &topic, const dds::core::status::InconsistentTopicStatus &status)=0

Detailed Description

template<typename T>
class dds::topic::TopicListener< T >

Topic events Listener.

Since a Topic is an Entity, it has the ability to have a Listener associated with it. In this case, the associated Listener should be of type TopicListener. This interface must be implemented by the application. A user-defined class must be provided by the application which must extend from the TopicListener class.

All operations for this interface must be implemented in the user-defined class, it is up to the application whether an operation is empty or contains some functionality.

The TopicListener provides a generic mechanism (actually a callback function) for the Data Distribution Service to notify the application of relevant asynchronous status change events, such as a missed deadline, violation of a QosPolicy setting, etc. The TopicListener is related to changes in communication status StatusConditions.

// Application example listener
class ExampleListener :
               public virtual dds::topic::TopicListener<Foo::Bar>
{
public:
    virtual void on_inconsistent_topic (
        dds::topic::Topic<Foo::Bar>& topic,
        const dds::core::status::InconsistentTopicStatus& status)
    {
        std::cout << "on_inconsistent_topic" << std::endl;
    }
};
 
// Create Topic with the listener
dds::domain::DomainParticipant participant(org::eclipse::cyclonedds::domain::default_id());
dds::topic::Topic<Foo::Bar> topic(participant,
                                  "TopicName",
                                  participant.default_topic_qos(),
                                  new ExampleListener(),
                                  dds::core::status::StatusMask::all());

See also

Topic

Listener information

Definition at line 39 of file Topic.hpp.

Member Function Documentation

on_inconsistent_topic()

template<typename T >

virtual void dds::topic::TopicListener< T >::on_inconsistent_topic ( Topic< T > &  topic, const dds::core::status::InconsistentTopicStatus &  status  )

pure virtual

This operation is called by the Data Distribution Service when the InconsistentTopicStatus changes.

The implementation may be left empty when this functionality is not needed. This operation will only be called when the relevant TopicListener is installed and enabled with the StatusMask::inconsistent_topic(). The InconsistentTopicStatus will change when another Topic exists with the same topic_name but different characteristics.

Parameters

topic	contain a pointer to the Topic on which the conflict occurred (this is an input to the application).
status	contain the InconsistentTopicStatus object (this is an input to the application).

---

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

• dds/topic/Topic.hpp
• dds/topic/TopicListener.hpp