| TopicSession.java |
/*
* JBoss, the OpenSource EJB server
*
* Distributable under LGPL license.
* See terms of license at gnu.org.
*/
package javax.jms;
/** A <CODE>TopicSession</CODE> object provides methods for creating
* <CODE>TopicPublisher</CODE>, <CODE>TopicSubscriber</CODE>, and
* <CODE>TemporaryTopic</CODE> objects. It also provides a method for
* deleting its client's durable subscribers.
*
*<P>A <CODE>TopicSession</CODE> is used for creating Pub/Sub specific
* objects. In general, use the <CODE>Session</CODE> object, and
* use <CODE>TopicSession</CODE> only to support
* existing code. Using the <CODE>Session</CODE> object simplifies the
* programming model, and allows transactions to be used across the two
* messaging domains.
*
* <P>A <CODE>TopicSession</CODE> cannot be used to create objects specific to the
* point-to-point domain. The following methods inherit from
* <CODE>Session</CODE>, but must throw an
* <CODE>IllegalStateException</CODE>
* if used from <CODE>TopicSession</CODE>:
*<UL>
* <LI><CODE>createBrowser</CODE>
* <LI><CODE>createQueue</CODE>
* <LI><CODE>createTemporaryQueue</CODE>
*</UL>
*
* @see javax.jms.Session
* @see javax.jms.Connection#createSession(boolean, int)
* @see javax.jms.TopicConnection#createTopicSession(boolean, int)
* @see javax.jms.XATopicSession#getTopicSession()
*/
public interface TopicSession extends Session {
/** Creates a topic identity given a <CODE>Topic</CODE> name.
*
* <P>This facility is provided for the rare cases where clients need to
* dynamically manipulate topic identity. This allows the creation of a
* topic identity with a provider-specific name. Clients that depend
* on this ability are not portable.
*
* <P>Note that this method is not for creating the physical topic.
* The physical creation of topics is an administrative task and is not
* to be initiated by the JMS API. The one exception is the
* creation of temporary topics, which is accomplished with the
* <CODE>createTemporaryTopic</CODE> method.
*
* @param topicName the name of this <CODE>Topic</CODE>
*
* @return a <CODE>Topic</CODE> with the given name
*
* @exception JMSException if the session fails to create a topic
* due to some internal error.
*/
Topic
createTopic(String topicName) throws JMSException;
/** Creates a nondurable subscriber to the specified topic.
*
* <P>A client uses a <CODE>TopicSubscriber</CODE> object to receive
* messages that have been published to a topic.
*
* <P>Regular <CODE>TopicSubscriber</CODE> objects are not durable.
* They receive only messages that are published while they are active.
*
* <P>In some cases, a connection may both publish and subscribe to a
* topic. The subscriber <CODE>NoLocal</CODE> attribute allows a subscriber
* to inhibit the delivery of messages published by its own connection.
* The default value for this attribute is false.
*
* @param topic the <CODE>Topic</CODE> to subscribe to
*
* @exception JMSException if the session fails to create a subscriber
* due to some internal error.
* @exception InvalidDestinationException if an invalid topic is specified.
*/
TopicSubscriber
createSubscriber(Topic topic) throws JMSException;
/** Creates a nondurable subscriber to the specified topic, using a
* message selector or specifying whether messages published by its
* own connection should be delivered to it.
*
* <P>A client uses a <CODE>TopicSubscriber</CODE> object to receive
* messages that have been published to a topic.
*
* <P>Regular <CODE>TopicSubscriber</CODE> objects are not durable.
* They receive only messages that are published while they are active.
*
* <P>Messages filtered out by a subscriber's message selector will
* never be delivered to the subscriber. From the subscriber's
* perspective, they do not exist.
*
* <P>In some cases, a connection may both publish and subscribe to a
* topic. The subscriber <CODE>NoLocal</CODE> attribute allows a subscriber
* to inhibit the delivery of messages published by its own connection.
* The default value for this attribute is false.
*
* @param topic the <CODE>Topic</CODE> to subscribe to
* @param messageSelector only messages with properties matching the
* message selector expression are delivered. A value of null or
* an empty string indicates that there is no message selector
* for the message consumer.
* @param noLocal if set, inhibits the delivery of messages published
* by its own connection
*
* @exception JMSException if the session fails to create a subscriber
* due to some internal error.
* @exception InvalidDestinationException if an invalid topic is specified.
* @exception InvalidSelectorException if the message selector is invalid.
*/
TopicSubscriber
createSubscriber(Topic topic,
String messageSelector,
boolean noLocal) throws JMSException;
/** Creates a durable subscriber to the specified topic.
*
* <P>If a client needs to receive all the messages published on a
* topic, including the ones published while the subscriber is inactive,
* it uses a durable <CODE>TopicSubscriber</CODE>. The JMS provider
* retains a record of this
* durable subscription and insures that all messages from the topic's
* publishers are retained until they are acknowledged by this
* durable subscriber or they have expired.
*
* <P>Sessions with durable subscribers must always provide the same
* client identifier. In addition, each client must specify a name that
* uniquely identifies (within client identifier) each durable
* subscription it creates. Only one session at a time can have a
* <CODE>TopicSubscriber</CODE> for a particular durable subscription.
*
* <P>A client can change an existing durable subscription by creating
* a durable <CODE>TopicSubscriber</CODE> with the same name and a new
* topic and/or
* message selector. Changing a durable subscriber is equivalent to
* unsubscribing (deleting) the old one and creating a new one.
*
* <P>In some cases, a connection may both publish and subscribe to a
* topic. The subscriber <CODE>NoLocal</CODE> attribute allows a subscriber
* to inhibit the delivery of messages published by its own connection.
* The default value for this attribute is false.
*
* @param topic the non-temporary <CODE>Topic</CODE> to subscribe to
* @param name the name used to identify this subscription
*
* @exception JMSException if the session fails to create a subscriber
* due to some internal error.
* @exception InvalidDestinationException if an invalid topic is specified.
*/
TopicSubscriber
createDurableSubscriber(Topic topic,
String name) throws JMSException;
/** Creates a durable subscriber to the specified topic, using a
* message selector or specifying whether messages published by its
* own connection should be delivered to it.
*
* <P>If a client needs to receive all the messages published on a
* topic, including the ones published while the subscriber is inactive,
* it uses a durable <CODE>TopicSubscriber</CODE>. The JMS provider
* retains a record of this
* durable subscription and insures that all messages from the topic's
* publishers are retained until they are acknowledged by this
* durable subscriber or they have expired.
*
* <P>Sessions with durable subscribers must always provide the same
* client identifier. In addition, each client must specify a name which
* uniquely identifies (within client identifier) each durable
* subscription it creates. Only one session at a time can have a
* <CODE>TopicSubscriber</CODE> for a particular durable subscription.
* An inactive durable subscriber is one that exists but
* does not currently have a message consumer associated with it.
*
* <P>A client can change an existing durable subscription by creating
* a durable <CODE>TopicSubscriber</CODE> with the same name and a new
* topic and/or
* message selector. Changing a durable subscriber is equivalent to
* unsubscribing (deleting) the old one and creating a new one.
*
* @param topic the non-temporary <CODE>Topic</CODE> to subscribe to
* @param name the name used to identify this subscription
* @param messageSelector only messages with properties matching the
* message selector expression are delivered. A value of null or
* an empty string indicates that there is no message selector
* for the message consumer.
* @param noLocal if set, inhibits the delivery of messages published
* by its own connection
*
* @exception JMSException if the session fails to create a subscriber
* due to some internal error.
* @exception InvalidDestinationException if an invalid topic is specified.
* @exception InvalidSelectorException if the message selector is invalid.
*/
TopicSubscriber
createDurableSubscriber(Topic topic,
String name,
String messageSelector,
boolean noLocal) throws JMSException;
/** Creates a publisher for the specified topic.
*
* <P>A client uses a <CODE>TopicPublisher</CODE> object to publish
* messages on a topic.
* Each time a client creates a <CODE>TopicPublisher</CODE> on a topic, it
* defines a
* new sequence of messages that have no ordering relationship with the
* messages it has previously sent.
*
* @param topic the <CODE>Topic</CODE> to publish to, or null if this is an
* unidentified producer
*
* @exception JMSException if the session fails to create a publisher
* due to some internal error.
* @exception InvalidDestinationException if an invalid topic is specified.
*/
TopicPublisher
createPublisher(Topic topic) throws JMSException;
/** Creates a <CODE>TemporaryTopic</CODE> object. Its lifetime will be that
* of the <CODE>TopicConnection</CODE> unless it is deleted earlier.
*
* @return a temporary topic identity
*
* @exception JMSException if the session fails to create a temporary
* topic due to some internal error.
*/
TemporaryTopic
createTemporaryTopic() throws JMSException;
/** Unsubscribes a durable subscription that has been created by a client.
*
* <P>This method deletes the state being maintained on behalf of the
* subscriber by its provider.
*
* <P>It is erroneous for a client to delete a durable subscription
* while there is an active <CODE>TopicSubscriber</CODE> for the
* subscription, or while a consumed message is part of a pending
* transaction or has not been acknowledged in the session.
*
* @param name the name used to identify this subscription
*
* @exception JMSException if the session fails to unsubscribe to the
* durable subscription due to some internal error.
* @exception InvalidDestinationException if an invalid subscription name
* is specified.
*/
void
unsubscribe(String name) throws JMSException;
}
| TopicSession.java |