eu.semaine.jms.sender
Class Sender

java.lang.Object
  eu.semaine.jms.IOBase
      eu.semaine.jms.sender.Sender

Direct Known Subclasses:

BytesSender, FeatureSender, XMLSender

public class Sender
extends IOBase

This class handles the common part to all message senders in the SEMAINE system.

Author:

marc

Nested Class Summary

Nested classes/interfaces inherited from class eu.semaine.jms.IOBase

IOBase.Event

Field Summary

protected java.lang.String	datatype The name of the data type being sent.
protected int	period If data is periodic, the period in which data is sent, in milliseconds.
protected javax.jms.MessageProducer	producer
protected java.lang.String	source The name of the source component from where the data originated.

Fields inherited from class eu.semaine.jms.IOBase

connection, isConnectionStarted, jmsPassword, jmsUrl, jmsUser, session, topic

Constructor Summary

Sender(java.lang.String topicName, java.lang.String datatype, java.lang.String source)
Create a new Sender to the given topic on the default JMS server.

Sender(java.lang.String jmsUrl, java.lang.String jmsUser, java.lang.String jmsPassword, java.lang.String topicName, java.lang.String datatype, java.lang.String source)
Create a new Sender to the given topic on the given JMS server.

Method Summary

protected void	fillMessageProperties(javax.jms.Message message, long usertime) Fill in the usual message properties as far as possible.
java.lang.String	getDatatype() The name of the data type sent.
int	getPeriod() For periodic senders, get the period of sending.
java.lang.String	getSource() The name of the source component sending the data.
long	getTimeToLive() Get the time to live for all messages sent by this sender, i.e. the number of milliseconds before the message is considered obsolete by the JMS system.
protected void	initialise(java.lang.String datatype, java.lang.String source)
boolean	isEventBased() Test whether this sender is set to send messages in an event-based way.
boolean	isPeriodic() Test whether this sender is set to send messages periodically.
static void	main(java.lang.String[] args)
void	sendTextMessage(java.lang.String text, long usertime) Send a text message via this sender.
void	sendTextMessage(java.lang.String text, long usertime, IOBase.Event eventType) Send a text message via this sender, for event-based messages.
void	setEventBased() Determine that the data is event-based, not periodic.
void	setPeriodic(int aPeriod) Determine that the data is periodic, and set the period in which data is (intended to be) sent, in milliseconds.
void	setTimeToLive(long aTimeToLive) Set the time to live for all messages sent by this sender, i.e. the number of milliseconds before the message is considered obsolete by the JMS system.

Methods inherited from class eu.semaine.jms.IOBase

getConnection, getJMSUrl, getSession, getTopic, getTopicName, startConnection

Methods inherited from class java.lang.Object

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

Field Detail

producer

protected javax.jms.MessageProducer producer

datatype

protected java.lang.String datatype

The name of the data type being sent.

source

protected java.lang.String source

The name of the source component from where the data originated.

period

protected int period

If data is periodic, the period in which data is sent, in milliseconds. A value of 0 means not periodic. Data can be either periodic or event-based, but not both at the same time.

Constructor Detail

Sender

public Sender(java.lang.String topicName,
              java.lang.String datatype,
              java.lang.String source)
       throws javax.jms.JMSException

Create a new Sender to the given topic on the default JMS server. The default JMS server is determined as follows:

• jms URL: read from system property jms.url, default value tcp://localhost:61616;
• jms User: read from system property jms.user, default value null;
• jms Password: read from system property jms.password, default value null.

Datatype and source will be sent with every message.

Parameters:

topic - the name of the topic to send to.

datatype - the name of the type of data being sent.

source - the name of the component sending the data.

Throws:

javax.jms.JMSException

java.lang.NullPointerException - if any of the parameters topicName, datatype, or source are null.

Sender

public Sender(java.lang.String jmsUrl,
              java.lang.String jmsUser,
              java.lang.String jmsPassword,
              java.lang.String topicName,
              java.lang.String datatype,
              java.lang.String source)
       throws javax.jms.JMSException

Create a new Sender to the given topic on the given JMS server. Datatype and source will be sent with every message.

Parameters:

jmsUrl - the url where to contact the JMS server

jmsUser - the username to use (can be null)

jmsPassword - the password to use (can be null)

topic - the name of the topic to send to.

datatype - the name of the type of data being sent.

source - the name of the component sending the data.

Throws:

javax.jms.JMSException

java.lang.NullPointerException - if any of the parameters jmsUrl, topicName, datatype, or source are null.

Method Detail

initialise

protected void initialise(java.lang.String datatype,
                          java.lang.String source)
                   throws javax.jms.JMSException

Throws:

javax.jms.JMSException

getDatatype

public java.lang.String getDatatype()

The name of the data type sent.

Returns:

a non-null and non-empty string.

getSource

public java.lang.String getSource()

The name of the source component sending the data.

Returns:

a non-null and non-empty string.

setPeriodic

public void setPeriodic(int aPeriod)

Determine that the data is periodic, and set the period in which data is (intended to be) sent, in milliseconds.

Parameters:

aPeriod - the period in which data is to be sent.

Throws:

java.lang.IllegalArgumentException - if aPeriod is <= 0.

setEventBased

public void setEventBased()

Determine that the data is event-based, not periodic. Individual messages can transport different kinds of events,

See Also:

#sendTextMessage(String, long, eu.semaine.jms.IOBase.Event)}.

isPeriodic

public boolean isPeriodic()

Test whether this sender is set to send messages periodically.

Returns:

true if sender is set to periodic, false otherwise.

isEventBased

public boolean isEventBased()

Test whether this sender is set to send messages in an event-based way.

Returns:

true if sender is set to event-based, false otherwise.

getPeriod

public int getPeriod()

For periodic senders, get the period of sending.

Returns:

An integer representing the period of sending, in milliseconds.

setTimeToLive

public void setTimeToLive(long aTimeToLive)
                   throws javax.jms.JMSException

Set the time to live for all messages sent by this sender, i.e. the number of milliseconds before the message is considered obsolete by the JMS system. Messages that are not delivered by their expiration time are deleted by the JMS system.

Parameters:

aTimeToLive - time to live, in milliseconds. A value of 0 means unlimited time, i.e. the messages will not expire.

Throws:

javax.jms.JMSException

getTimeToLive

public long getTimeToLive()
                   throws javax.jms.JMSException

Get the time to live for all messages sent by this sender, i.e. the number of milliseconds before the message is considered obsolete by the JMS system. Messages that are not delivered by their expiration time are deleted by the JMS system.

Returns:

time to live, in milliseconds. A value of 0 means unlimited time, i.e. the messages will not expire.

Throws:

javax.jms.JMSException

sendTextMessage

public void sendTextMessage(java.lang.String text,
                            long usertime)
                     throws javax.jms.JMSException

Send a text message via this sender. This will send a message to the registered topic with the following message properties:

• datatype is a String property containing the value produced by getDatatype();
• source is a String property containing the value produced by getSource();
• usertime is a long property containing the value of parameter usertime;
• if the message is periodic (isPeriodic() returns true), period is an int property containing the value returned by getPeriod();
• else, the message is event-based. event is a String property; as this method does not specify an event type, the default value single is assumed.

Furthermore, if getTimeToLive() returns a non-zero value, the message will contain a header field JMSExpiration containing the time when the message will expire.

Parameters:

text - the message text.

usertime - the "user" time that this message refers to, in milliseconds since 1970.

Throws:

java.lang.IllegalStateException - if the connection is not started or the sender is in event-based mode.

javax.jms.JMSException

sendTextMessage

public void sendTextMessage(java.lang.String text,
                            long usertime,
                            IOBase.Event eventType)
                     throws javax.jms.JMSException

Send a text message via this sender, for event-based messages. This will send a message to the registered topic with the following message properties:

• datatype is a String property containing the value produced by getDatatype();
• source is a String property containing the value produced by getSource();
• usertime is a long property containing the value of parameter usertime;
• event is a String property containing the String representation of the event parameter to this method.

Furthermore, if getTimeToLive() returns a non-zero value, the message will contain a header field JMSExpiration containing the time when the message will expire.

Parameters:

text - the message text.

usertime - the "user" time that this message refers to, in milliseconds since 1970.

event - the type of event represented by this message.

Throws:

java.lang.IllegalStateException - if the connection is not started or the sender is in periodic mode.

javax.jms.JMSException

fillMessageProperties

protected void fillMessageProperties(javax.jms.Message message,
                                     long usertime)
                              throws javax.jms.JMSException

Fill in the usual message properties as far as possible. Subclasses are encouraged to override this method, but should normally call this method as well (as super.fillMessageProperties(message, usertime)).

Parameters:

a - message object in preparation for sending.

usertime - the "user" time that this message refers to, in milliseconds since 1970.

Throws:

javax.jms.JMSException

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Throws:

java.lang.Exception