A Session 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 JMS object.
A session serves several purposes:
TemporaryTopics and
TemporaryQueues.
Queue or Topic
objects for those clients that need to dynamically manipulate
provider-specific destination names.
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 the Session's MessageProducers.
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's rollback 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 JMS sessions, etc.). Since Java distributed
transactions are controlled via the Java Transaction API (JTA), use of the
session's commit and rollback methods in
this context is prohibited.
The JMS API does not require support for JTA; however, it does define how a provider supplies this support.
Although it is also possible for a JMS client to handle distributed transactions directly, it is unlikely that many JMS clients will do this. Support for JTA in the JMS API is targeted at systems vendors who will be integrating the JMS API into their application server products.
javax.jms.QueueSession, javax.jms.TopicSession, javax.jms.XASession
| Modifier and Type | Field and Description |
|---|---|
| public 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 to |
| public static final int | CLIENT_ACKNOWLEDGE
With this acknowledgment mode, the client acknowledges a consumed
message by calling the message's |
| public static final int | DUPS_OK_ACKNOWLEDGE
This acknowledgment mode instructs the session to lazily acknowledge the delivery of messages. |
| public static final int | SESSION_TRANSACTED
This value may be passed as the argument to the
method |
| Modifier and Type | Method and Description |
|---|---|
| public void | |
| public void | |
| public QueueBrowser | createBrowser(Queue
the queue)queue to accessCreates a |
| public QueueBrowser | createBrowser(Queue
the queue, String queue to accessonly 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. messageSelector)Creates a |
| public BytesMessage | |
| public MessageConsumer | createConsumer(Destination
the destination)Destination to access.Creates a |
| public MessageConsumer | createConsumer(Destination
the destination, String Destination to accessonly 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. messageSelector)Creates a |
| public MessageConsumer | createConsumer(Destination
the destination, String Destination to accessonly 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. messageSelector, boolean - if true, and the destination is a topic,
then the noLocal)MessageConsumer will
not receive messages published to the topic
by its own connection.Creates a |
| public MessageConsumer | createDurableConsumer(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name)Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription. |
| public MessageConsumer | createDurableConsumer(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name, String 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. messageSelector, boolean 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. noLocal)Creates an unshared durable subscription on the specified topic (if one
does not already exist), specifying a message selector and the
|
| public TopicSubscriber | createDurableSubscriber(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name)Creates an unshared durable subscription on the specified topic (if one does not already exist) and creates a consumer on that durable subscription. |
| public TopicSubscriber | createDurableSubscriber(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name, String 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. messageSelector, boolean 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. noLocal)Creates an unshared durable subscription on the specified topic (if one
does not already exist), specifying a message selector and the
|
| public MapMessage | |
| public Message | |
| public ObjectMessage | |
| public ObjectMessage | createObjectMessage(Serializable
the object to use to initialize this message object)Creates an initialized |
| public MessageProducer | createProducer(Destination
the destination)Destination to send to,
or null if this is a producer which does not have a specified
destination.Creates a |
| public Queue | Returns: a Queue object which encapsulates the specified nameA provider-specific queue name queueName)Creates a |
| public MessageConsumer | createSharedConsumer(Topic
the topic, String Topic to subscribe tothe name used to identify the shared non-durable subscription 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. |
| public MessageConsumer | createSharedConsumer(Topic
the topic, String Topic to subscribe tothe name used to identify the shared non-durable subscription sharedSubscriptionName, String 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. 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. |
| public MessageConsumer | createSharedDurableConsumer(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name)Creates a shared durable subscription on the specified topic (if one does
not already exist), specifying a message selector and the |
| public MessageConsumer | createSharedDurableConsumer(Topic
the non-temporary topic, String Topic to subscribe tothe name used to identify this subscription name, String 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. 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. |
| public StreamMessage | |
| public TemporaryQueue | |
| public TemporaryTopic | |
| public TextMessage | |
| public TextMessage | createTextMessage(String
the string used to initialize this message text)Creates an initialized |
| public Topic | Returns: a Topic object which encapsulates the specified nameA provider-specific topic name topicName)Creates a |
| public int | Returns: If the session is not transacted, returns the current acknowledgement mode for the session. If the session is transacted, returns SESSION_TRANSACTED.Returns the acknowledgement mode of the session. |
| public MessageListener | Returns: the distinguished message listener associated with this sessionReturns the session's distinguished message listener (optional). |
| public boolean | Returns: true if the session is in transacted modeIndicates whether the session is in transacted mode. |
| public void | recover()
Stops message delivery in this session, and restarts message delivery with the oldest unacknowledged message. |
| public void | |
| public void | run()
Redeclares java. |
| public void | setMessageListener(MessageListener
the message listener to associate with this session listener)Sets the session's distinguished message listener (optional). |
| public void | unsubscribe(String
the name used to identify this subscription name)Unsubscribes a durable subscription that has been created by a client. |
| AUTO_ACKNOWLEDGE | back to summary |
|---|---|
| public 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 to | |
| CLIENT_ACKNOWLEDGE | back to summary |
|---|---|
| public static final int CLIENT_ACKNOWLEDGE With this acknowledgment mode, the client acknowledges a consumed
message by calling the message's When client acknowledgment mode is used, a client may build up a large number of unacknowledged messages while attempting to process them. A JMS 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.
| |
| DUPS_OK_ACKNOWLEDGE | back to summary |
|---|---|
| public 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 JMS 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. | |
| SESSION_TRANSACTED | back to summary |
|---|---|
| public static final int SESSION_TRANSACTED This value may be passed as the argument to the
method
This value is returned from the method
| |
| close | back to summary |
|---|---|
| public void close() throws JMSException Redeclares java. 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
However if the close method is called from a message listener
on its own
Since two alternative behaviors are permitted in this case,
applications should avoid calling close from a message listener on
its own 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 Closing a transacted session must roll back the transaction in progress.
This method is the only A CompletionListener callback method must not call close on its own Session. Doing so will cause an IllegalStateException to be thrown.
Invoking any other
| |
| commit | back to summary |
|---|---|
| public 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.
| |
| createBrowser | back to summary |
|---|---|
| public QueueBrowser createBrowser(Queue queue) throws JMSException Creates a
| |
| createBrowser | back to summary |
|---|---|
| public QueueBrowser createBrowser(Queue queue, String messageSelector) throws JMSException Creates a
| |
| createBytesMessage | back to summary |
|---|---|
| public BytesMessage createBytesMessage() throws JMSException Creates a
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createConsumer | back to summary |
|---|---|
| public MessageConsumer createConsumer(Destination destination) throws JMSException Creates a
| |
| createConsumer | back to summary |
|---|---|
| public MessageConsumer createConsumer(Destination destination, String messageSelector) throws JMSException Creates a A client uses a
| |
| createConsumer | back to summary |
|---|---|
| public MessageConsumer createConsumer(Destination destination, String messageSelector, boolean noLocal) throws JMSException Creates a Since A client uses a The
| |
| createDurableConsumer | back to summary |
|---|---|
| public 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 a 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 JMS 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
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
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
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
If an unshared durable subscription already exists with the same name and
client identifier but a different topic, message selector or
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 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 | back to summary |
|---|---|
| public 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 the
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 JMS 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
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
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
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
If an unshared durable subscription already exists with the same name and
client identifier but a different topic, message selector or
If
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 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 | back to summary |
|---|---|
| public 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 a 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 JMS 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
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
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
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
If an unshared durable subscription already exists with the same name and
client identifier but a different topic, message selector or
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 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 | back to summary |
|---|---|
| public 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 the
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 JMS 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
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
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
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
If an unshared durable subscription already exists with the same name and
client identifier but a different topic, message selector or
If
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 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
| |
| createMapMessage | back to summary |
|---|---|
| public MapMessage createMapMessage() throws JMSException Creates a
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createMessage | back to summary |
|---|---|
| public Message createMessage() throws JMSException Creates a
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createObjectMessage | back to summary |
|---|---|
| public ObjectMessage createObjectMessage() throws JMSException Creates an
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createObjectMessage | back to summary |
|---|---|
| public ObjectMessage createObjectMessage(Serializable object) throws JMSException Creates an initialized
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createProducer | back to summary |
|---|---|
| public MessageProducer createProducer(Destination destination) throws JMSException Creates a A client uses a
| |
| createQueue | back to summary |
|---|---|
| public Queue createQueue(String queueName) throws JMSException Creates a
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
Note that this method simply creates an object that encapsulates the name
of a queue. It does not create the physical queue in the JMS provider.
JMS does not provide a method to create the physical queue, since this
would be specific to a given JMS 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
| |
| createSharedConsumer | back to summary |
|---|---|
| public 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
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 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 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.
| |
| createSharedConsumer | back to summary |
|---|---|
| public 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
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 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 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.
| |
| createSharedDurableConsumer | back to summary |
|---|---|
| public 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 the 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 JMS 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
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
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
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
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 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.
| |
| createSharedDurableConsumer | back to summary |
|---|---|
| public 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 JMS 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
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
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
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
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 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.
| |
| createStreamMessage | back to summary |
|---|---|
| public StreamMessage createStreamMessage() throws JMSException Creates a
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
| |
| createTemporaryQueue | back to summary |
|---|---|
| public TemporaryQueue createTemporaryQueue() throws JMSException Creates a
| |
| createTemporaryTopic | back to summary |
|---|---|
| public TemporaryTopic createTemporaryTopic() throws JMSException Creates a
| |
| createTextMessage | back to summary |
|---|---|
| public TextMessage createTextMessage() throws JMSException Creates a
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
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| createTextMessage | back to summary |
|---|---|
| public TextMessage createTextMessage(String text) throws JMSException Creates an initialized
The message object returned may be sent using any The message object returned may be optimised for use with the JMS provider used to create it. However it can be sent using any JMS provider, not just the JMS provider used to create it.
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| createTopic | back to summary |
|---|---|
| public Topic createTopic(String topicName) throws JMSException Creates a
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
Note that this method simply creates an object that encapsulates the name
of a topic. It does not create the physical topic in the JMS provider.
JMS does not provide a method to create the physical topic, since this
would be specific to a given JMS 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
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| getAcknowledgeMode | back to summary |
|---|---|
| public 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.
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| getMessageListener | back to summary |
|---|---|
| public MessageListener getMessageListener() throws JMSException Returns the session's distinguished message listener (optional).
This method must not be used in a Java EE web or EJB application.
Doing so may cause a
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| getTransacted | back to summary |
|---|---|
| public boolean getTransacted() throws JMSException Indicates whether the session is in transacted mode.
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| recover | back to summary |
|---|---|
| public 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:
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| rollback | back to summary |
|---|---|
| public 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.
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| run | back to summary |
|---|---|
| public void run() Redeclares java. Optional operation, intended to be used only by Application Servers, not by ordinary JMS clients.
This method must not be used in a Java EE web or EJB application.
Doing so may cause a
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| setMessageListener | back to summary |
|---|---|
| public 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 JMS clients.
This method must not be used in a Java EE web or EJB application.
Doing so may cause a
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| unsubscribe | back to summary |
|---|---|
| public 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.
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