ros.tools

Class PeriodicPublisher

java.lang.Object

ros.tools.PeriodicPublisher

public class PeriodicPublisher
extends Object

This class is a tool for causing a ROS message to be periodically published at a given rate. To start periodic publishing use the beginPublishing(int) or beginPublishing(Object, int) methods. Note that subsequent calls to these method will automatically cancel the previous periodic publishing and start again at the newly specified rate. To cancel periodic publishing, use the cancelPublishing() method. You can also change the message that is being published without stopping or restarting the publishing by using the setMsg(Object) method.

Author:

James MacGlashan.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	PeriodicPublisher.PublisherTimerTask The class that is called by Java's Timer and invokes the actual publish call.

Field Summary

Fields

Modifier and Type	Field and Description
protected Object	msg The ROS message that will be periodically published
protected int	period The period at which this object is publishing; -1 if it is not currently publishing.
protected Publisher	pub The Publisher to which publish calls are made
protected PeriodicPublisher.PublisherTimerTask	timerTask The timer task that calls the publish.

Constructor Summary

Constructors

Constructor and Description
PeriodicPublisher(Publisher pub) Initializes with a Publisher for publishing action messages to ROS.
PeriodicPublisher(Publisher pub, Object msg) Initializes with a Publisher for publishing action messages to ROS.
PeriodicPublisher(String topic, String msgType, RosBridge rosBridge) Initializes with a Publisher for this action using the specified topic, message type, and RosBridge connection.
PeriodicPublisher(String topic, String msgType, RosBridge rosBridge, Object msg) Initializes with a Publisher for this action using the specified topic, message type, and RosBridge connection.

Method Summary

Modifier and Type	Method and Description
void	beginPublishing(int period) Causes this object to begin periodically publishing at the specified rate.
void	beginPublishing(Object msg, int period) Causes this object to begin periodically publishing the specified message at the specified rate.
void	cancelPublishing() Stops this object from periodically publishing, or does nothing if it is not currently periodically publishing.
Object	getMsg() Returns the ROS message that is being or will be periodically published.
Publisher	getPub()
int	getPublishingPeriod() The delay in milliseconds between subsequent periodic publishes.
boolean	isPublishing() Indicates whether this object is currently periodically publishing.
void	setMsg(Object msg) Sets the ROS message that will be periodically published.
void	setPub(Publisher pub)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

pub

protected Publisher pub

The Publisher to which publish calls are made

msg

protected volatile Object msg

The ROS message that will be periodically published

period

protected int period

The period at which this object is publishing; -1 if it is not currently publishing.

timerTask

protected PeriodicPublisher.PublisherTimerTask timerTask

The timer task that calls the publish. Null if this object is not periodically publishing.

Constructor Detail

PeriodicPublisher

public PeriodicPublisher(String topic,
                         String msgType,
                         RosBridge rosBridge)

Initializes with a Publisher for this action using the specified topic, message type, and RosBridge connection.

Parameters:

topic - the ros topic to which messages will be published

msgType - the ros message type of th target topic

rosBridge - the RosBridge connection to use.

PeriodicPublisher

public PeriodicPublisher(String topic,
                         String msgType,
                         RosBridge rosBridge,
                         Object msg)

Initializes with a Publisher for this action using the specified topic, message type, and RosBridge connection.

Parameters:

topic - the ros topic to which messages will be published

msgType - the ros message type of th target topic

rosBridge - the RosBridge connection to use.

msg - the ROS message to periodically publish when publishing begins

PeriodicPublisher

public PeriodicPublisher(Publisher pub)

Initializes with a Publisher for publishing action messages to ROS.

Parameters:

pub - the Publisher to which to publish

PeriodicPublisher

public PeriodicPublisher(Publisher pub,
                         Object msg)

Initializes with a Publisher for publishing action messages to ROS.

Parameters:

pub - the Publisher to which to publish

msg - the ROS message to periodically publish when publishing begins

Method Detail

getPub

public Publisher getPub()

setPub

public void setPub(Publisher pub)

getMsg

public Object getMsg()

Returns the ROS message that is being or will be periodically published.

Returns:

the ROS message that is being or will be periodically published.

setMsg

public void setMsg(Object msg)

Sets the ROS message that will be periodically published. Note that if the provided message is null and this object is already periodically publishing, a runtime error will be thrown.

Parameters:

msg - the ROS message that will be published.

getPublishingPeriod

public int getPublishingPeriod()

The delay in milliseconds between subsequent periodic publishes. Returns -1 if this object is not currently periodically publishing.

Returns:

The delay in milliseconds between subsequent publishes. Returns -1 if this object is not currently periodically publishing.

cancelPublishing

public void cancelPublishing()

Stops this object from periodically publishing, or does nothing if it is not currently periodically publishing.

isPublishing

public boolean isPublishing()

Indicates whether this object is currently periodically publishing.

Returns:

true if this object is periodically publishing; false if it is not.

beginPublishing

public void beginPublishing(int period)

Causes this object to begin periodically publishing at the specified rate. If this object is already publishing then the previous publishing rate is canceled and started at the new rate. If the current message to publish is not set, then a runtime exception will be thrown. The message can be set either with the setMsg(Object) method or by using the alternative beginPublishing(Object, int) method that takes the message to publish.

Parameters:

period - the time in milliseconds between publishes

beginPublishing

public void beginPublishing(Object msg,
                            int period)

Causes this object to begin periodically publishing the specified message at the specified rate. If this object is already publishing then the previous publishing rate is canceled and started at the new rate. Note that if the provided message is null then a runtime exception will be thrown.

Parameters:

msg - the ROS message to publish

period - the time in milliseconds between publishes