-
- All Superinterfaces:
AutoCloseable
,Runnable
- All Known Subinterfaces:
QueueSession
,TopicSession
,XAQueueSession
,XASession
,XATopicSession
public interface Session extends Runnable, AutoCloseable
ASession
object is a single-threaded context for producing and consuming messages. Although it may allocate provider resources outside the Java virtual machine (JVM), it is considered a lightweight Jakarta Messaging object.A session serves several purposes:
- It is a factory for its message producers and consumers.
- It supplies provider-optimized message factories.
- It is a factory for
TemporaryTopics
andTemporaryQueues
. - It provides a way to create
Queue
orTopic
objects for those clients that need to dynamically manipulate provider-specific destination names. - It supports a single series of transactions that combine work spanning its producers and consumers into atomic units.
- It defines a serial order for the messages it consumes and the messages it produces.
- It retains messages it consumes until they have been acknowledged.
- It serializes execution of message listeners registered with its message consumers.
- It is a factory for
QueueBrowsers
.
A session can create and service multiple message producers and consumers.
One typical use is to have a thread block on a synchronous
MessageConsumer
until a message arrives. The thread may then use one or more of theSession
'sMessageProducer
s.If a client desires to have one thread produce messages while others consume them, the client should use a separate session for its producing thread.
Once a connection has been started, any session with one or more registered message listeners is dedicated to the thread of control that delivers messages to it. It is erroneous for client code to use this session or any of its constituent objects from another thread of control. The only exception to this rule is the use of the session or message consumer
close
method.It should be easy for most clients to partition their work naturally into sessions. This model allows clients to start simply and incrementally add message processing complexity as their need for concurrency grows.
The
close
method is the only session method that can be called while some other session method is being executed in another thread.A session may be specified as transacted. Each transacted session supports a single series of transactions. Each transaction groups a set of message sends and a set of message receives into an atomic unit of work. In effect, transactions organize a session's input message stream and output message stream into series of atomic units. When a transaction commits, its atomic unit of input is acknowledged and its associated atomic unit of output is sent. If a transaction rollback is done, the transaction's sent messages are destroyed and the session's input is automatically recovered.
The content of a transaction's input and output units is simply those messages that have been produced and consumed within the session's current transaction.
A transaction is completed using either its session's
commit
method or its session'srollback
method. The completion of a session's current transaction automatically begins the next. The result is that a transacted session always has a current transaction within which its work is done.The Java Transaction Service (JTS) or some other transaction monitor may be used to combine a session's transaction with transactions on other resources (databases, other Jakarta Messaging sessions, etc.). Since Java distributed transactions are controlled via the Java Transaction API (JTA), use of the session's
commit
androllback
methods in this context is prohibited.The Jakarta Messaging API does not require support for JTA; however, it does define how a provider supplies this support.
Although it is also possible for a Jakarta Messaging client to handle distributed transactions directly, it is unlikely that many Jakarta Messaging clients will do this. Support for JTA in the Jakarta Messaging API is targeted at systems vendors who will be integrating the Jakarta Messaging API into their application server products.
- Since:
- JMS 1.0
- Version:
- Jakarta Messaging 2.0
- See Also:
QueueSession
,TopicSession
,XASession
-
-
Field Summary
Fields Modifier and Type Field Description static int
AUTO_ACKNOWLEDGE
With this acknowledgment mode, the session automatically acknowledges a client's receipt of a message either when the session has successfully returned from a call toreceive
or when the message listener the session has called to process the message successfully returns.static int
CLIENT_ACKNOWLEDGE
With this acknowledgment mode, the client acknowledges a consumed message by calling the message'sacknowledge
method.static int
DUPS_OK_ACKNOWLEDGE
This acknowledgment mode instructs the session to lazily acknowledge the delivery of messages.static int
SESSION_TRANSACTED
This value may be passed as the argument to the methodcreateSession(int sessionMode)
on theConnection
object to specify that the session should use a local transaction.
-
Method Summary
All Methods Instance Methods Abstract Methods Modifier and Type Method Description void
close()
Closes the session.void
commit()
Commits all messages done in this transaction and releases any locks currently held.QueueBrowser
createBrowser(Queue queue)
Creates aQueueBrowser
object to peek at the messages on the specified queue.QueueBrowser
createBrowser(Queue queue, String messageSelector)
Creates aQueueBrowser
object to peek at the messages on the specified queue using a message selector.BytesMessage
createBytesMessage()
Creates aBytesMessage
object.MessageConsumer
createConsumer(Destination destination)
Creates aMessageConsumer
for the specified destination.MessageConsumer
createConsumer(Destination destination, String messageSelector)
Creates aMessageConsumer
for the specified destination, using a message selector.MessageConsumer
createConsumer(Destination destination, String messageSelector, boolean noLocal)
Creates aMessageConsumer
for the specified destination, specifying a message selector and thenoLocal
parameter.MessageConsumer
createDurableConsumer(Topic topic, String name)
Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription.MessageConsumer
createDurableConsumer(Topic topic, String name, String messageSelector, boolean noLocal)
Creates an unshared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription.TopicSubscriber
createDurableSubscriber(Topic topic, String name)
Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription.TopicSubscriber
createDurableSubscriber(Topic topic, String name, String messageSelector, boolean noLocal)
Creates an unshared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription.MapMessage
createMapMessage()
Creates aMapMessage
object.Message
createMessage()
Creates aMessage
object.ObjectMessage
createObjectMessage()
Creates anObjectMessage
object.ObjectMessage
createObjectMessage(Serializable object)
Creates an initializedObjectMessage
object.MessageProducer
createProducer(Destination destination)
Creates aMessageProducer
to send messages to the specified destination.Queue
createQueue(String queueName)
Creates aQueue
object which encapsulates a specified provider-specific queue name.MessageConsumer
createSharedConsumer(Topic topic, String sharedSubscriptionName)
Creates a shared non-durable subscription with the specified name on the specified topic (if one does not already exist) and creates a consumer on that subscription.MessageConsumer
createSharedConsumer(Topic topic, String sharedSubscriptionName, String messageSelector)
Creates a shared non-durable subscription with the specified name on the specified topic (if one does not already exist) specifying a message selector, and creates a consumer on that subscription.MessageConsumer
createSharedDurableConsumer(Topic topic, String name)
Creates a shared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription.MessageConsumer
createSharedDurableConsumer(Topic topic, String name, String messageSelector)
Creates a shared durable subscription on the specified topic (if one does not already exist), specifying a message selector, and creates a consumer on that durable subscription.StreamMessage
createStreamMessage()
Creates aStreamMessage
object.TemporaryQueue
createTemporaryQueue()
Creates aTemporaryQueue
object.TemporaryTopic
createTemporaryTopic()
Creates aTemporaryTopic
object.TextMessage
createTextMessage()
Creates aTextMessage
object.TextMessage
createTextMessage(String text)
Creates an initializedTextMessage
object.Topic
createTopic(String topicName)
Creates aTopic
object which encapsulates a specified provider-specific topic name.int
getAcknowledgeMode()
Returns the acknowledgement mode of the session.MessageListener
getMessageListener()
Returns the session's distinguished message listener (optional).boolean
getTransacted()
Indicates whether the session is in transacted mode.void
recover()
Stops message delivery in this session, and restarts message delivery with the oldest unacknowledged message.void
rollback()
Rolls back any messages done in this transaction and releases any locks currently held.void
run()
Optional operation, intended to be used only by Application Servers, not by ordinary Jakarta Messaging clients.void
setMessageListener(MessageListener listener)
Sets the session's distinguished message listener (optional).void
unsubscribe(String name)
Unsubscribes a durable subscription that has been created by a client.
-
-
-
Field Detail
-
AUTO_ACKNOWLEDGE
static final int AUTO_ACKNOWLEDGE
With this acknowledgment mode, the session automatically acknowledges a client's receipt of a message either when the session has successfully returned from a call toreceive
or when the message listener the session has called to process the message successfully returns.- See Also:
- Constant Field Values
-
CLIENT_ACKNOWLEDGE
static final int CLIENT_ACKNOWLEDGE
With this acknowledgment mode, the client acknowledges a consumed message by calling the message'sacknowledge
method. Acknowledging a consumed message acknowledges all messages that the session has consumed.When client acknowledgment mode is used, a client may build up a large number of unacknowledged messages while attempting to process them. A Jakarta Messaging provider should provide administrators with a way to limit client overrun so that clients are not driven to resource exhaustion and ensuing failure when some resource they are using is temporarily blocked.
- See Also:
Message.acknowledge()
, Constant Field Values
-
DUPS_OK_ACKNOWLEDGE
static final int DUPS_OK_ACKNOWLEDGE
This acknowledgment mode instructs the session to lazily acknowledge the delivery of messages. This is likely to result in the delivery of some duplicate messages if the Jakarta Messaging provider fails, so it should only be used by consumers that can tolerate duplicate messages. Use of this mode can reduce session overhead by minimizing the work the session does to prevent duplicates.- See Also:
- Constant Field Values
-
SESSION_TRANSACTED
static final int SESSION_TRANSACTED
This value may be passed as the argument to the methodcreateSession(int sessionMode)
on theConnection
object to specify that the session should use a local transaction.This value is returned from the method
getAcknowledgeMode
if the session is using a local transaction, irrespective of whether the session was created by calling the methodcreateSession(int sessionMode)
or the methodcreateSession(boolean transacted, int acknowledgeMode)
.- Since:
- JMS 1.1
- See Also:
- Constant Field Values
-
-
Method Detail
-
createBytesMessage
BytesMessage createBytesMessage() throws JMSException
Creates aBytesMessage
object. ABytesMessage
object is used to send a message containing a stream of uninterpreted bytes.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
BytesMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createMapMessage
MapMessage createMapMessage() throws JMSException
Creates aMapMessage
object. AMapMessage
object is used to send a self-defining set of name-value pairs, where names areString
objects and values are primitive values in the Java programming language.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
MapMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createMessage
Message createMessage() throws JMSException
Creates aMessage
object. TheMessage
interface is the root interface of all Jakarta Messaging messages. AMessage
object holds all the standard message header information. It can be sent when a message containing only header information is sufficient.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
Message
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createObjectMessage
ObjectMessage createObjectMessage() throws JMSException
Creates anObjectMessage
object. AnObjectMessage
object is used to send a message that contains a serializable Java object.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
ObjectMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createObjectMessage
ObjectMessage createObjectMessage(Serializable object) throws JMSException
Creates an initializedObjectMessage
object. AnObjectMessage
object is used to send a message that contains a serializable Java object.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Parameters:
object
- the object to use to initialize this message- Returns:
- A
ObjectMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createStreamMessage
StreamMessage createStreamMessage() throws JMSException
Creates aStreamMessage
object. AStreamMessage
object is used to send a self-defining stream of primitive values in the Java programming language.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
StreamMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createTextMessage
TextMessage createTextMessage() throws JMSException
Creates aTextMessage
object. ATextMessage
object is used to send a message containing aString
object.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Returns:
- A
TextMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
createTextMessage
TextMessage createTextMessage(String text) throws JMSException
Creates an initializedTextMessage
object. ATextMessage
object is used to send a message containing aString
.The message object returned may be sent using any
Session
orJMSContext
. It is not restricted to being sent using theJMSContext
used to create it.The message object returned may be optimised for use with the Jakarta Messaging provider used to create it. However it can be sent using any Jakarta Messaging provider, not just the Jakarta Messaging provider used to create it.
- Parameters:
text
- the string used to initialize this message- Returns:
- A
TextMessage
object. - Throws:
JMSException
- if the Jakarta Messaging provider fails to create this message due to some internal error.
-
getTransacted
boolean getTransacted() throws JMSException
Indicates whether the session is in transacted mode.- Returns:
- true if the session is in transacted mode
- Throws:
JMSException
- if the Jakarta Messaging provider fails to return the transaction mode due to some internal error.
-
getAcknowledgeMode
int getAcknowledgeMode() throws JMSException
Returns the acknowledgement mode of the session. The acknowledgement mode is set at the time that the session is created. If the session is transacted, the acknowledgement mode is ignored.- Returns:
- If the session is not transacted, returns the current acknowledgement mode for the session. If the session is transacted, returns SESSION_TRANSACTED.
- Throws:
JMSException
- if the Jakarta Messaging provider fails to return the acknowledgment mode due to some internal error.- Since:
- JMS 1.1
- See Also:
Connection.createSession(boolean, int)
-
commit
void commit() throws JMSException
Commits all messages done in this transaction and releases any locks currently held.This method must not return until any incomplete asynchronous send operations for this Session have been completed and any CompletionListener callbacks have returned. Incomplete sends should be allowed to complete normally unless an error occurs.
A CompletionListener callback method must not call commit on its own Session. Doing so will cause an IllegalStateException to be thrown.
- Throws:
IllegalStateException
-- the session is not using a local transaction
- this method has been called by a CompletionListener callback method on its own Session
JMSException
- if the Jakarta Messaging provider fails to commit the transaction due to some internal error.TransactionRolledBackException
- if the transaction is rolled back due to some internal error during commit.
-
rollback
void rollback() throws JMSException
Rolls back any messages done in this transaction and releases any locks currently held.This method must not return until any incomplete asynchronous send operations for this Session have been completed and any CompletionListener callbacks have returned. Incomplete sends should be allowed to complete normally unless an error occurs.
A CompletionListener callback method must not call commit on its own Session. Doing so will cause an IllegalStateException to be thrown.
- Throws:
IllegalStateException
-- the session is not using a local transaction
- this method has been called by a CompletionListener callback method on its own Session
JMSException
- if the Jakarta Messaging provider fails to roll back the transaction due to some internal error.
-
close
void close() throws JMSException
Closes the session.Since a provider may allocate some resources on behalf of a session outside the JVM, clients should close the resources when they are not needed. Relying on garbage collection to eventually reclaim these resources may not be timely enough.
There is no need to close the producers and consumers of a closed session.
This call will block until a
receive
call or message listener in progress has completed. A blocked message consumerreceive
call returnsnull
when this session is closed.However if the close method is called from a message listener on its own
Session
, then it will either fail and throw ajakarta.jms.IllegalStateException
, or it will succeed and close theSession
, blocking until any pending receive call in progress has completed. If close succeeds and the acknowledge mode of theSession
is set toAUTO_ACKNOWLEDGE
, the current message will still be acknowledged automatically when theonMessage
call completes.Since two alternative behaviors are permitted in this case, applications should avoid calling close from a message listener on its own
Session
because this is not portable.This method must not return until any incomplete asynchronous send operations for this Session have been completed and any CompletionListener callbacks have returned. Incomplete sends should be allowed to complete normally unless an error occurs.
For the avoidance of doubt, if an exception listener for this session's connection is running when
close
is invoked, there is no requirement for theclose
call to wait until the exception listener has returned before it may return.Closing a transacted session must roll back the transaction in progress.
This method is the only
Session
method that can be called concurrently.A CompletionListener callback method must not call close on its own Session. Doing so will cause an IllegalStateException to be thrown.
Invoking any other
Session
method on a closed session must throw aIllegalStateException
. Closing a closed session must not throw an exception.- Specified by:
close
in interfaceAutoCloseable
- Throws:
IllegalStateException
-- this method has been called by a MessageListener on its own Session
- this method has been called by a CompletionListener callback method on its own Session
JMSException
- if the Jakarta Messaging provider fails to close the session due to some internal error.
-
recover
void recover() throws JMSException
Stops message delivery in this session, and restarts message delivery with the oldest unacknowledged message.All consumers deliver messages in a serial order. Acknowledging a received message automatically acknowledges all messages that have been delivered to the client.
Restarting a session causes it to take the following actions:
- Stop message delivery
- Mark all messages that might have been delivered but not acknowledged as "redelivered"
- Restart the delivery sequence including all unacknowledged messages that had been previously delivered. Redelivered messages do not have to be delivered in exactly their original delivery order.
- Throws:
JMSException
- if the Jakarta Messaging provider fails to stop and restart message delivery due to some internal error.IllegalStateException
- if the method is called by a transacted session.
-
getMessageListener
MessageListener getMessageListener() throws JMSException
Returns the session's distinguished message listener (optional).This method must not be used in a Jakarta EE web or EJB application. Doing so may cause a
JMSException
to be thrown though this is not guaranteed.- Returns:
- the distinguished message listener associated with this session
- Throws:
JMSException
- if the Jakarta Messaging provider fails to get the session's distinguished message listener for one of the following reasons:- an internal error has occurred
- this method has been called in a Jakarta EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)
- See Also:
setMessageListener(jakarta.jms.MessageListener)
,ServerSessionPool
,ServerSession
-
setMessageListener
void setMessageListener(MessageListener listener) throws JMSException
Sets the session's distinguished message listener (optional).When the distinguished message listener is set, no other form of message receipt in the session can be used; however, all forms of sending messages are still supported.
This is an expert facility not used by ordinary Jakarta Messaging clients.
This method must not be used in a Jakarta EE web or EJB application. Doing so may cause a
JMSException
to be thrown though this is not guaranteed.- Parameters:
listener
- the message listener to associate with this session- Throws:
JMSException
- if the Jakarta Messaging provider fails to set the session's distinguished message listener for one of the following reasons:- an internal error has occurred
- this method has been called in a Jakarta EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)
- See Also:
getMessageListener()
,ServerSessionPool
,ServerSession
-
run
void run()
Optional operation, intended to be used only by Application Servers, not by ordinary Jakarta Messaging clients.This method must not be used in a Jakarta EE web or EJB application. Doing so may cause a
JMSRuntimeException
to be thrown though this is not guaranteed.- Specified by:
run
in interfaceRunnable
- Throws:
JMSRuntimeException
- if this method has been called in a Jakarta EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)- See Also:
ServerSession
-
createProducer
MessageProducer createProducer(Destination destination) throws JMSException
Creates aMessageProducer
to send messages to the specified destination.A client uses a
MessageProducer
object to send messages to a destination. SinceQueue
andTopic
both inherit fromDestination
, they can be used in the destination parameter to create aMessageProducer
object.- Parameters:
destination
- theDestination
to send to, or null if this is a producer which does not have a specified destination.- Returns:
- A
MessageProducer
to send messages. - Throws:
JMSException
- if the session fails to create a MessageProducer due to some internal error.InvalidDestinationException
- if an invalid destination is specified.- Since:
- JMS 1.1
-
createConsumer
MessageConsumer createConsumer(Destination destination) throws JMSException
Creates aMessageConsumer
for the specified destination. SinceQueue
andTopic
both inherit fromDestination
, they can be used in the destination parameter to create aMessageConsumer
.- Parameters:
destination
- theDestination
to access.- Returns:
- A
MessageConsumer
for the specified destination. - Throws:
JMSException
- if the session fails to create a consumer due to some internal error.InvalidDestinationException
- if an invalid destination is specified.- Since:
- JMS 1.1
-
createConsumer
MessageConsumer createConsumer(Destination destination, String messageSelector) throws JMSException
Creates aMessageConsumer
for the specified destination, using a message selector. SinceQueue
andTopic
both inherit fromDestination
, they can be used in the destination parameter to create aMessageConsumer
.A client uses a
MessageConsumer
object to receive messages that have been sent to a destination.- Parameters:
destination
- theDestination
to accessmessageSelector
- 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.- Returns:
- A
MessageConsumer
for the specified destination. - Throws:
JMSException
- if the session fails to create a MessageConsumer due to some internal error.InvalidDestinationException
- if an invalid destination is specified.InvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 1.1
-
createConsumer
MessageConsumer createConsumer(Destination destination, String messageSelector, boolean noLocal) throws JMSException
Creates aMessageConsumer
for the specified destination, specifying a message selector and thenoLocal
parameter.Since
Queue
andTopic
both inherit fromDestination
, they can be used in the destination parameter to create aMessageConsumer
.A client uses a
MessageConsumer
object to receive messages that have been published to a destination.The
noLocal
argument is for use when the destination is a topic and the session's connection is also being used to publish messages to that topic. IfnoLocal
is set to true then theMessageConsumer
will not receive messages published to the topic by its own connection. The default value of this argument is false. If the destination is a queue then the effect of settingnoLocal
to true is not specified.- Parameters:
destination
- theDestination
to accessmessageSelector
- 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.noLocal
- - if true, and the destination is a topic, then theMessageConsumer
will not receive messages published to the topic by its own connection.- Returns:
- A
MessageConsumer
for the specified destination. - Throws:
JMSException
- if the session fails to create a MessageConsumer due to some internal error.InvalidDestinationException
- if an invalid destination is specified.InvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 1.1
-
createSharedConsumer
MessageConsumer createSharedConsumer(Topic topic, String sharedSubscriptionName) throws JMSException
Creates a shared non-durable subscription with the specified name on the specified topic (if one does not already exist) and creates a consumer on that subscription. This method creates the non-durable subscription without a message selector.If a shared non-durable subscription already exists with the same name and client identifier (if set), and the same topic and message selector value has been specified, then this method creates a
MessageConsumer
on the existing subscription.A non-durable shared subscription is used by a client which needs to be able to share the work of receiving messages from a topic subscription amongst multiple consumers. A non-durable shared subscription may therefore have more than one consumer. Each message from the subscription will be delivered to only one of the consumers on that subscription. Such a subscription is not persisted and will be deleted (together with any undelivered messages associated with it) when there are no consumers on it. The term "consumer" here means a
MessageConsumer
orJMSConsumer
object in any client.A shared non-durable subscription is identified by a name specified by the client and by the client identifier (which may be unset). An application which subsequently wishes to create a consumer on that shared non-durable subscription must use the same client identifier.
If a shared non-durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is a consumer already active (i.e. not closed) on the subscription, then a
JMSException
will be thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId (which may be unset). Such subscriptions would be completely separate.
- Parameters:
topic
- theTopic
to subscribe tosharedSubscriptionName
- the name used to identify the shared non-durable subscription- Returns:
- A shared non-durable subscription with the specified name on the specified topic.
- Throws:
JMSException
- if the session fails to create the shared non-durable subscription andMessageConsumer
due to some internal error.InvalidDestinationException
- if an invalid topic is specified.InvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 2.0
-
createSharedConsumer
MessageConsumer createSharedConsumer(Topic topic, String sharedSubscriptionName, String messageSelector) throws JMSException
Creates a shared non-durable subscription with the specified name on the specified topic (if one does not already exist) specifying a message selector, and creates a consumer on that subscription.If a shared non-durable subscription already exists with the same name and client identifier (if set), and the same topic and message selector has been specified, then this method creates a
MessageConsumer
on the existing subscription.A non-durable shared subscription is used by a client which needs to be able to share the work of receiving messages from a topic subscription amongst multiple consumers. A non-durable shared subscription may therefore have more than one consumer. Each message from the subscription will be delivered to only one of the consumers on that subscription. Such a subscription is not persisted and will be deleted (together with any undelivered messages associated with it) when there are no consumers on it. The term "consumer" here means a
MessageConsumer
orJMSConsumer
object in any client.A shared non-durable subscription is identified by a name specified by the client and by the client identifier (which may be unset). An application which subsequently wishes to create a consumer on that shared non-durable subscription must use the same client identifier.
If a shared non-durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is a consumer already active (i.e. not closed) on the subscription, then a
JMSException
will be thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId (which may be unset). Such subscriptions would be completely separate.
- Parameters:
topic
- theTopic
to subscribe tosharedSubscriptionName
- the name used to identify the shared non-durable subscriptionmessageSelector
- only messages with properties matching the message selector expression are added to the shared non-durable subscription. A value of null or an empty string indicates that there is no message selector for the shared non-durable subscription.- Returns:
- A shared non-durable subscription with the specified name on the specified topic.
- Throws:
JMSException
- if the session fails to create the shared non-durable subscription andMessageConsumer
due to some internal error.InvalidDestinationException
- if an invalid topic is specified.InvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 2.0
-
createQueue
Queue createQueue(String queueName) throws JMSException
Creates aQueue
object which encapsulates a specified provider-specific queue name.The use of provider-specific queue names in an application may render the application non-portable. Portable applications are recommended to not use this method but instead look up an administratively-defined
Queue
object using JNDI.Note that this method simply creates an object that encapsulates the name of a queue. It does not create the physical queue in the Jakarta Messaging provider. Jakarta Messaging does not provide a method to create the physical queue, since this would be specific to a given Jakarta Messaging provider. Creating a physical queue is provider-specific and is typically an administrative task performed by an administrator, though some providers may create them automatically when needed. The one exception to this is the creation of a temporary queue, which is done using the
createTemporaryQueue
method.- Parameters:
queueName
- A provider-specific queue name- Returns:
- a Queue object which encapsulates the specified name
- Throws:
JMSException
- if a Queue object cannot be created due to some internal error
-
createTopic
Topic createTopic(String topicName) throws JMSException
Creates aTopic
object which encapsulates a specified provider-specific topic name.The use of provider-specific topic names in an application may render the application non-portable. Portable applications are recommended to not use this method but instead look up an administratively-defined
Topic
object using JNDI.Note that this method simply creates an object that encapsulates the name of a topic. It does not create the physical topic in the Jakarta Messaging provider. Jakarta Messaging does not provide a method to create the physical topic, since this would be specific to a given Jakarta Messaging provider. Creating a physical topic is provider-specific and is typically an administrative task performed by an administrator, though some providers may create them automatically when needed. The one exception to this is the creation of a temporary topic, which is done using the
createTemporaryTopic
method.- Parameters:
topicName
- A provider-specific topic name- Returns:
- a Topic object which encapsulates the specified name
- Throws:
JMSException
- if a Topic object cannot be created due to some internal error
-
createDurableSubscriber
TopicSubscriber createDurableSubscriber(Topic topic, String name) throws JMSException
Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription. This method creates the durable subscription without a message selector and with anoLocal
value offalse
.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with unshared durable subscriptions. Any durable subscription created using this method will be unshared. This means that only one active (i.e. not closed) consumer on the subscription may exist at a time. The term "consumer" here means a
TopicSubscriber
,MessageConsumer
orJMSConsumer
object in any client.An unshared durable subscription is identified by a name specified by the client and by the client identifier, which must be set. An application which subsequently wishes to create a consumer on that unshared durable subscription must use the same client identifier.
If an unshared durable subscription already exists with the same name and client identifier, and the same topic, message selector and
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this method creates aTopicSubscriber
on the existing durable subscription.If an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.If an unshared durable subscription already exists with the same name and client identifier but a different topic, message selector or
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier. If a shared durable subscription already exists with the same name and client identifier then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId. Such subscriptions would be completely separate.
This method is identical to the corresponding
createDurableConsumer
method except that it returns aTopicSubscriber
rather than aMessageConsumer
to represent the consumer.- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscription- Returns:
- An unshared durable subscription on the specified topic.
- Throws:
InvalidDestinationException
- if an invalid topic is specified.IllegalStateException
- if the client identifier is unsetJMSException
-- if the session fails to create the unshared durable subscription and
TopicSubscriber
due to some internal error - if an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active
- if a shared durable subscription already exists with the same name and client identifier
- if the session fails to create the unshared durable subscription and
- Since:
- JMS 1.1
-
createDurableSubscriber
TopicSubscriber createDurableSubscriber(Topic topic, String name, String messageSelector, boolean noLocal) throws JMSException
Creates an unshared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with unshared durable subscriptions. Any durable subscription created using this method will be unshared. This means that only one active (i.e. not closed) consumer on the subscription may exist at a time. The term "consumer" here means a
TopicSubscriber
,MessageConsumer
orJMSConsumer
object in any client.An unshared durable subscription is identified by a name specified by the client and by the client identifier, which must be set. An application which subsequently wishes to create a consumer on that unshared durable subscription must use the same client identifier.
If an unshared durable subscription already exists with the same name and client identifier, and the same topic, message selector and
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this method creates aTopicSubscriber
on the existing durable subscription.If an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.If an unshared durable subscription already exists with the same name and client identifier but a different topic, message selector or
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.If
noLocal
is set to true then any messages published to the topic using this session's connection, or any other connection with the same client identifier, will not be added to the durable subscription.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier. If a shared durable subscription already exists with the same name and client identifier then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId. Such subscriptions would be completely separate.
This method is identical to the corresponding
createDurableConsumer
method except that it returns aTopicSubscriber
rather than aMessageConsumer
to represent the consumer.- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscriptionmessageSelector
- only messages with properties matching the message selector expression are added to the durable subscription. A value of null or an empty string indicates that there is no message selector for the durable subscription.noLocal
- if true then any messages published to the topic using this session's connection, or any other connection with the same client identifier, will not be added to the durable subscription.- Returns:
- An unshared durable subscription on the specified topic.
- Throws:
InvalidDestinationException
- if an invalid topic is specified.InvalidSelectorException
- if the message selector is invalid.IllegalStateException
- if the client identifier is unsetJMSException
-- if the session fails to create the unshared durable subscription and
TopicSubscriber
due to some internal error - if an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active
- if a shared durable subscription already exists with the same name and client identifier
- if the session fails to create the unshared durable subscription and
- Since:
- JMS 1.1
-
createDurableConsumer
MessageConsumer createDurableConsumer(Topic topic, String name) throws JMSException
Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription. This method creates the durable subscription without a message selector and with anoLocal
value offalse
.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with unshared durable subscriptions. Any durable subscription created using this method will be unshared. This means that only one active (i.e. not closed) consumer on the subscription may exist at a time. The term "consumer" here means a
TopicSubscriber
,MessageConsumer
orJMSConsumer
object in any client.An unshared durable subscription is identified by a name specified by the client and by the client identifier, which must be set. An application which subsequently wishes to create a consumer on that unshared durable subscription must use the same client identifier.
If an unshared durable subscription already exists with the same name and client identifier, and the same topic, message selector and
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this method creates aMessageConsumer
on the existing durable subscription.If an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.If an unshared durable subscription already exists with the same name and client identifier but a different topic, message selector or
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier. If a shared durable subscription already exists with the same name and client identifier then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId. Such subscriptions would be completely separate.
This method is identical to the corresponding
createDurableSubscriber
method except that it returns aMessageConsumer
rather than aTopicSubscriber
to represent the consumer.- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscription- Returns:
- An unshared durable subscription on the specified topic.
- Throws:
InvalidDestinationException
- if an invalid topic is specified.IllegalStateException
- if the client identifier is unsetJMSException
-- if the session fails to create the unshared durable subscription and
MessageConsumer
due to some internal error - if an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active
- if a shared durable subscription already exists with the same name and client identifier
- if the session fails to create the unshared durable subscription and
- Since:
- JMS 2.0
-
createDurableConsumer
MessageConsumer createDurableConsumer(Topic topic, String name, String messageSelector, boolean noLocal) throws JMSException
Creates an unshared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with unshared durable subscriptions. Any durable subscription created using this method will be unshared. This means that only one active (i.e. not closed) consumer on the subscription may exist at a time. The term "consumer" here means a
TopicSubscriber
,MessageConsumer
orJMSConsumer
object in any client.An unshared durable subscription is identified by a name specified by the client and by the client identifier, which must be set. An application which subsequently wishes to create a consumer on that unshared durable subscription must use the same client identifier.
If an unshared durable subscription already exists with the same name and client identifier, and the same topic, message selector and
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this method creates aMessageConsumer
on the existing durable subscription.If an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.If an unshared durable subscription already exists with the same name and client identifier but a different topic, message selector or
noLocal
value has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.If
noLocal
is set to true then any messages published to the topic using this session's connection, or any other connection with the same client identifier, will not be added to the durable subscription.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier. If a shared durable subscription already exists with the same name and client identifier then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId. Such subscriptions would be completely separate.
This method is identical to the corresponding
createDurableSubscriber
method except that it returns aMessageConsumer
rather than aTopicSubscriber
to represent the consumer.- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscriptionmessageSelector
- only messages with properties matching the message selector expression are added to the durable subscription. A value of null or an empty string indicates that there is no message selector for the durable subscription.noLocal
- if true then any messages published to the topic using this session's connection, or any other connection with the same client identifier, will not be added to the durable subscription.- Returns:
- An unshared durable subscription on the specified topic.
- Throws:
InvalidDestinationException
- if an invalid topic is specified.InvalidSelectorException
- if the message selector is invalid.IllegalStateException
- if the client identifier is unsetJMSException
-- if the session fails to create the unshared durable subscription and
MessageConsumer
due to some internal error - if an unshared durable subscription already exists with the same name and client identifier, and there is a consumer already active
- if a shared durable subscription already exists with the same name and client identifier
- if the session fails to create the unshared durable subscription and
- Since:
- JMS 2.0
-
createSharedDurableConsumer
MessageConsumer createSharedDurableConsumer(Topic topic, String name) throws JMSException
Creates a shared durable subscription on the specified topic (if one does not already exist), specifying a message selector and thenoLocal
parameter, and creates a consumer on that durable subscription. This method creates the durable subscription without a message selector.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with shared durable subscriptions. Any durable subscription created using this method will be shared. This means that multiple active (i.e. not closed) consumers on the subscription may exist at the same time. The term "consumer" here means a
MessageConsumer
orJMSConsumer
object in any client.A shared durable subscription is identified by a name specified by the client and by the client identifier (which may be unset). An application which subsequently wishes to create a consumer on that shared durable subscription must use the same client identifier.
If a shared durable subscription already exists with the same name and client identifier (if set), and the same topic and message selector has been specified, then this method creates a
MessageConsumer
on the existing shared durable subscription.If a shared durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.
If a shared durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier (if set). If an unshared durable subscription already exists with the same name and client identifier (if set) then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId (which may be unset). Such subscriptions would be completely separate.
- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscription- Returns:
- A shared durable subscription on the specified topic.
- Throws:
JMSException
-- if the session fails to create the shared durable subscription and
MessageConsumer
due to some internal error - if a shared durable subscription already exists with the same name and client identifier, but a different topic or message selector, and there is a consumer already active
- if an unshared durable subscription already exists with the same name and client identifier
- if the session fails to create the shared durable subscription and
InvalidDestinationException
- if an invalid topic is specified.- Since:
- JMS 2.0
-
createSharedDurableConsumer
MessageConsumer createSharedDurableConsumer(Topic topic, String name, String messageSelector) throws JMSException
Creates a shared durable subscription on the specified topic (if one does not already exist), specifying a message selector, and creates a consumer on that durable subscription.A durable subscription is used by an application which needs to receive all the messages published on a topic, including the ones published when there is no active consumer associated with it. The Jakarta Messaging provider retains a record of this durable subscription and ensures that all messages from the topic's publishers are retained until they are delivered to, and acknowledged by, a consumer on this durable subscription or until they have expired.
A durable subscription will continue to accumulate messages until it is deleted using the
unsubscribe
method.This method may only be used with shared durable subscriptions. Any durable subscription created using this method will be shared. This means that multiple active (i.e. not closed) consumers on the subscription may exist at the same time. The term "consumer" here means a
MessageConsumer
orJMSConsumer
object in any client.A shared durable subscription is identified by a name specified by the client and by the client identifier (which may be unset). An application which subsequently wishes to create a consumer on that shared durable subscription must use the same client identifier.
If a shared durable subscription already exists with the same name and client identifier (if set), and the same topic and message selector has been specified, then this method creates a
MessageConsumer
on the existing shared durable subscription.If a shared durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is no consumer already active (i.e. not closed) on the durable subscription then this is equivalent to unsubscribing (deleting) the old one and creating a new one.
If a shared durable subscription already exists with the same name and client identifier (if set) but a different topic or message selector has been specified, and there is a consumer already active (i.e. not closed) on the durable subscription, then a
JMSException
will be thrown.A shared durable subscription and an unshared durable subscription may not have the same name and client identifier (if set). If an unshared durable subscription already exists with the same name and client identifier (if set) then a
JMSException
is thrown.There is no restriction on durable subscriptions and shared non-durable subscriptions having the same name and clientId (which may be unset). Such subscriptions would be completely separate.
- Parameters:
topic
- the non-temporaryTopic
to subscribe toname
- the name used to identify this subscriptionmessageSelector
- only messages with properties matching the message selector expression are added to the durable subscription. A value of null or an empty string indicates that there is no message selector for the durable subscription.- Returns:
- A shared durable subscription on the specified topic.
- Throws:
JMSException
-- if the session fails to create the shared durable subscription and
MessageConsumer
due to some internal error - if a shared durable subscription already exists with the same name and client identifier, but a different topic or message selector, and there is a consumer already active
- if an unshared durable subscription already exists with the same name and client identifier
- if the session fails to create the shared durable subscription and
InvalidDestinationException
- if an invalid topic is specified.InvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 2.0
-
createBrowser
QueueBrowser createBrowser(Queue queue) throws JMSException
Creates aQueueBrowser
object to peek at the messages on the specified queue.- Parameters:
queue
- thequeue
to access- Returns:
- A
QueueBrowser
object to peek at the messages on the specified queue. - Throws:
JMSException
- if the session fails to create a browser due to some internal error.InvalidDestinationException
- if an invalid destination is specified- Since:
- JMS 1.1
-
createBrowser
QueueBrowser createBrowser(Queue queue, String messageSelector) throws JMSException
Creates aQueueBrowser
object to peek at the messages on the specified queue using a message selector.- Parameters:
queue
- thequeue
to accessmessageSelector
- 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.- Returns:
- A
QueueBrowser
object to peek at the messages on the specified queue. - Throws:
JMSException
- if the session fails to create a browser due to some internal error.InvalidDestinationException
- if an invalid destination is specifiedInvalidSelectorException
- if the message selector is invalid.- Since:
- JMS 1.1
-
createTemporaryQueue
TemporaryQueue createTemporaryQueue() throws JMSException
Creates aTemporaryQueue
object. Its lifetime will be that of theConnection
unless it is deleted earlier.- Returns:
- a temporary queue identity
- Throws:
JMSException
- if the session fails to create a temporary queue due to some internal error.- Since:
- JMS 1.1
-
createTemporaryTopic
TemporaryTopic createTemporaryTopic() throws JMSException
Creates aTemporaryTopic
object. Its lifetime will be that of theConnection
unless it is deleted earlier.- Returns:
- a temporary topic identity
- Throws:
JMSException
- if the session fails to create a temporary topic due to some internal error.- Since:
- JMS 1.1
-
unsubscribe
void unsubscribe(String name) throws JMSException
Unsubscribes a durable subscription that has been created by a client.This method deletes the state being maintained on behalf of the subscriber by its provider.
A durable subscription is identified by a name specified by the client and by the client identifier if set. If the client identifier was set when the durable subscription was created then a client which subsequently wishes to use this method to delete a durable subscription must use the same client identifier.
It is erroneous for a client to delete a durable subscription while there is an active (not closed) consumer for the subscription, or while a consumed message is part of a pending transaction or has not been acknowledged in the session.
- Parameters:
name
- the name used to identify this subscription- Throws:
JMSException
- if the session fails to unsubscribe to the durable subscription due to some internal error.InvalidDestinationException
- if an invalid subscription name is specified.- Since:
- JMS 1.1
-
-