Package org.ros.node.topic

Interface Publisher<T>

Type Parameters:

T - the Publisher may only publish messages of this type

All Superinterfaces:

TopicParticipant

All Known Implementing Classes:

DefaultPublisher

public interface Publisher<T>
extends TopicParticipant

Publishes messages of a given type on a given ROS topic.

Author:

ethan.rublee@gmail.com (Ethan Rublee), damonkohler@google.com (Damon Kohler)

Method Summary

Modifier and Type	Method	Description
void	addListener(PublisherListener<T> listener)	Add a new lifecycle listener to the Publisher.
boolean	getLatchMode()
int	getNumberOfSubscribers()	Get the number of Subscribers currently connected to the Publisher.
boolean	hasSubscribers()
T	newMessage()	Create a new message.
void	publish(T message)	Publishes a message.
void	setLatchMode(boolean enabled)
void	shutdown()	Shuts down and unregisters the Publisher using the default timeout for PublisherListener.onShutdown(Publisher) callbacks.
void	shutdown(long timeout, TimeUnit unit)	Shuts down and unregisters the Publisher.

Methods inherited from interface org.ros.internal.node.topic.TopicParticipant

getTopicMessageType, getTopicName

Method Details

setLatchMode

void setLatchMode(boolean enabled)

Parameters:

enabled - true if published messages should be latched, false otherwise

See Also:

• Publisher options documentation

getLatchMode

boolean getLatchMode()

Returns:

true if published messages will be latched, false otherwise

See Also:

• Publisher options documentation

newMessage

T newMessage()

Create a new message.

Returns:

a new message

publish

void publish(T message)

Publishes a message. This message will be available on the topic that this Publisher has been associated with.

Parameters:

message - the message to publish

hasSubscribers

boolean hasSubscribers()

Returns:

true if getNumberOfSubscribers() > 0, false otherwise

getNumberOfSubscribers

int getNumberOfSubscribers()

Get the number of Subscribers currently connected to the Publisher.

This counts the number of Subscriber registered. If a Subscriber does not shutdown properly it will not be unregistered and thus will contribute to this count.

Returns:

the number of Subscribers currently connected to the Publisher

shutdown

void shutdown(long timeout,
 TimeUnit unit)

Shuts down and unregisters the Publisher. Shutdown is delayed by at most the specified timeout to allow PublisherListener.onShutdown(Publisher) callbacks to complete.

PublisherListener.onShutdown(Publisher) callbacks are executed in separate threads.

shutdown

void shutdown()

Shuts down and unregisters the Publisher using the default timeout for PublisherListener.onShutdown(Publisher) callbacks.

PublisherListener.onShutdown(Publisher) callbacks are executed in separate threads.

See Also:

• shutdown(long, TimeUnit)

addListener

void addListener(PublisherListener<T> listener)

Add a new lifecycle listener to the Publisher.

Parameters:

listener - the PublisherListener to add