javax.jms

Interface JMSContext

All Superinterfaces:

AutoCloseable

All Known Subinterfaces:

XAJMSContext

All Known Implementing Classes:

ActiveMQJMSContext, ActiveMQXAJMSContext

public interface JMSContext
extends AutoCloseable

A JMSContext is the main interface in the simplified JMS API introduced for JMS 2.0. This combines in a single object the functionality of two separate objects from the JMS 1.1 API: a Connection and a Session.

When an application needs to send messages it use the createProducer method to create a JMSProducer which provides methods to configure and send messages. Messages may be sent either synchronously or asynchronously.

When an application needs to receive messages it uses one of several createConsumer or createDurableConsumer methods to create a JMSConsumer . A JMSConsumer provides methods to receive messages either synchronously or asynchronously.

In terms of the JMS 1.1 API a JMSContext should be thought of as representing both a Connection and a Session. Although the simplified API removes the need for applications to use those objects, the concepts of connection and session remain important. A connection represents a physical link to the JMS server and a session represents a single-threaded context for sending and receiving messages.

A JMSContext may be created by calling one of several createContext methods on a ConnectionFactory. A JMSContext that is created in this way is described as being application-managed. An application-managed JMSContext must be closed when no longer needed by calling its close method.

Applications running in the Java EE web and EJB containers may alternatively inject a JMSContext into their application using the @Inject annotation. A JMSContext that is created in this way is described as being container-managed. A container-managed JMSContext will be closed automatically by the container.

Applications running in the Java EE web and EJB containers are not permitted to create more than one active session on a connection so combining them in a single object takes advantage of this restriction to offer a simpler API.

However applications running in a Java SE environment or in the Java EE application client container are permitted to create multiple active sessions on the same connection. This allows the same physical connection to be used in multiple threads simultaneously. Such applications which require multiple sessions to be created on the same connection should use one of the createContext methods on the ConnectionFactory to create the first JMSContext and then use the createContext method on JMSContext to create additional JMSContext objects that use the same connection. All these JMSContext objects are application-managed and must be closed when no longer needed by calling their close method.

Since:

JMS 2.0

Version:

JMS 2.0

Field Summary

Fields

Modifier and Type	Field and Description
static int	AUTO_ACKNOWLEDGE With this session mode, the JMSContext's session automatically acknowledges a client's receipt of a message either when the session has successfully returned from a call to receive or when the message listener the session has called to process the message successfully returns.
static int	CLIENT_ACKNOWLEDGE With this session mode, the client acknowledges a consumed message by calling the message's acknowledge method.
static int	DUPS_OK_ACKNOWLEDGE This session mode instructs the JMSContext's session to lazily acknowledge the delivery of messages.
static int	SESSION_TRANSACTED This session mode instructs the JMSContext's session to deliver and consume messages in a local transaction which will be subsequently committed by calling commit or rolled back by calling rollback.

Method Summary

Modifier and Type	Method and Description
void	acknowledge() Acknowledges all messages consumed by the JMSContext's session.
void	close() Closes the JMSContext
void	commit() Commits all messages done in this transaction and releases any locks currently held.
QueueBrowser	createBrowser(Queue queue) Creates a QueueBrowser object to peek at the messages on the specified queue.
QueueBrowser	createBrowser(Queue queue, String messageSelector) Creates a QueueBrowser object to peek at the messages on the specified queue using a message selector.
BytesMessage	createBytesMessage() Creates a BytesMessage object.
JMSConsumer	createConsumer(Destination destination) Creates a JMSConsumer for the specified destination.
JMSConsumer	createConsumer(Destination destination, String messageSelector) Creates a JMSConsumer for the specified destination, using a message selector.
JMSConsumer	createConsumer(Destination destination, String messageSelector, boolean noLocal) Creates a JMSConsumer for the specified destination, specifying a message selector and the noLocal parameter.
JMSContext	createContext(int sessionMode) Creates a new JMSContext with the specified session mode using the same connection as this JMSContext and creating a new session.
JMSConsumer	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.
JMSConsumer	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 the noLocal parameter, and creates a consumer on that durable subscription.
MapMessage	createMapMessage() Creates a MapMessage object.
Message	createMessage() Creates a Message object.
ObjectMessage	createObjectMessage() Creates an ObjectMessage object.
ObjectMessage	createObjectMessage(Serializable object) Creates an initialized ObjectMessage object.
JMSProducer	createProducer() Creates a new JMSProducer object which can be used to configure and send messages
Queue	createQueue(String queueName) Creates a Queue object which encapsulates a specified provider-specific queue name.
JMSConsumer	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.
JMSConsumer	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.
JMSConsumer	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 creates a consumer on that durable subscription.
JMSConsumer	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 a StreamMessage object.
TemporaryQueue	createTemporaryQueue() Creates a TemporaryQueue object.
TemporaryTopic	createTemporaryTopic() Creates a TemporaryTopic object.
TextMessage	createTextMessage() Creates a TextMessage object.
TextMessage	createTextMessage(String text) Creates an initialized TextMessage object.
Topic	createTopic(String topicName) Creates a Topic object which encapsulates a specified provider-specific topic name.
boolean	getAutoStart() Returns whether the underlying connection used by this JMSContext will be started automatically when a consumer is created.
String	getClientID() Gets the client identifier for the JMSContext's connection.
ExceptionListener	getExceptionListener() Gets the ExceptionListener object for the JMSContext's connection.
ConnectionMetaData	getMetaData() Gets the connection metadata for the JMSContext's connection.
int	getSessionMode() Returns the session mode of the JMSContext's session.
boolean	getTransacted() Indicates whether the JMSContext's session is in transacted mode.
void	recover() Stops message delivery in the JMSContext's 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	setAutoStart(boolean autoStart) Specifies whether the underlying connection used by this JMSContext will be started automatically when a consumer is created.
void	setClientID(String clientID) Sets the client identifier for the JMSContext's connection.
void	setExceptionListener(ExceptionListener listener) Sets an exception listener for the JMSContext's connection.
void	start() Starts (or restarts) delivery of incoming messages by the JMSContext's connection.
void	stop() Temporarily stops the delivery of incoming messages by the JMSContext's connection.
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 session mode, the JMSContext's session automatically acknowledges a client's receipt of a message either when the session has successfully returned from a call to receive 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 session mode, the client acknowledges a consumed message by calling the message's acknowledge method. Acknowledging a consumed message acknowledges all messages that the session has consumed.

When this session 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.

See Also:

Message.acknowledge(), Constant Field Values

DUPS_OK_ACKNOWLEDGE

static final int DUPS_OK_ACKNOWLEDGE

This session mode instructs the JMSContext's 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.

See Also:

Constant Field Values

SESSION_TRANSACTED

static final int SESSION_TRANSACTED

This session mode instructs the JMSContext's session to deliver and consume messages in a local transaction which will be subsequently committed by calling commit or rolled back by calling rollback.

See Also:

Constant Field Values

Method Detail

createContext

JMSContext createContext(int sessionMode)

Creates a new JMSContext with the specified session mode using the same connection as this JMSContext and creating a new session.

This method does not start the connection. If the connection has not already been started then it will be automatically started when a JMSConsumer is created on any of the JMSContext objects for that connection.

• If sessionMode is set to JMSContext.SESSION_TRANSACTED then the session will use a local transaction which may subsequently be committed or rolled back by calling the JMSContext's commit or rollback methods.
• If sessionMode is set to any of JMSContext.CLIENT_ACKNOWLEDGE, JMSContext.AUTO_ACKNOWLEDGE or JMSContext.DUPS_OK_ACKNOWLEDGE. then the session will be non-transacted and messages received by this session will be acknowledged according to the value of sessionMode. For a definition of the meaning of these acknowledgement modes see the links below.

This method must not be used by applications running in the Java EE web or EJB containers because doing so would violate the restriction that such an application must not attempt to create more than one active (not closed) Session object per connection. If this method is called in a Java EE web or EJB container then a JMSRuntimeException will be thrown.

Parameters:

sessionMode - indicates which of four possible session modes will be used. The permitted values are JMSContext.SESSION_TRANSACTED, JMSContext.CLIENT_ACKNOWLEDGE, JMSContext.AUTO_ACKNOWLEDGE and JMSContext.DUPS_OK_ACKNOWLEDGE.

Returns:

a newly created JMSContext

Throws:

JMSRuntimeException - if the JMS provider fails to create the JMSContext due to

• some internal error or
• because this method is being called in a Java EE web or EJB application.

Since:

JMS 2.0

See Also:

SESSION_TRANSACTED, CLIENT_ACKNOWLEDGE, AUTO_ACKNOWLEDGE, DUPS_OK_ACKNOWLEDGE, ConnectionFactory.createContext(), ConnectionFactory.createContext(int), ConnectionFactory.createContext(java.lang.String, java.lang.String), ConnectionFactory.createContext(java.lang.String, java.lang.String, int), createContext(int)

createProducer

JMSProducer createProducer()

Creates a new JMSProducer object which can be used to configure and send messages

Returns:

A new JMSProducer object

See Also:

JMSProducer

getClientID

String getClientID()

Gets the client identifier for the JMSContext's connection.

This value is specific to the JMS provider. It is either preconfigured by an administrator in a ConnectionFactory object or assigned dynamically by the application by calling the setClientID method.

Returns:

the unique client identifier

Throws:

JMSRuntimeException - if the JMS provider fails to return the client ID for the JMSContext's connection due to some internal error.

setClientID

void setClientID(String clientID)

Sets the client identifier for the JMSContext's connection.

The preferred way to assign a JMS client's client identifier is for it to be configured in a client-specific ConnectionFactory object and transparently assigned to the Connection object it creates.

Alternatively, a client can set the client identifier for the MessageContext's connection using a provider-specific value. The facility to set its client identifier explicitly is not a mechanism for overriding the identifier that has been administratively configured. It is provided for the case where no administratively specified identifier exists. If one does exist, an attempt to change it by setting it must throw an IllegalStateRuntimeException. If a client sets the client identifier explicitly, it must do so immediately after it creates the JMSContext and before any other action on the JMSContext is taken. After this point, setting the client identifier is a programming error that should throw an IllegalStateRuntimeException.

The purpose of the client identifier is to associate the JMSContext's connection and its objects with a state maintained on behalf of the client by a provider. The only such state identified by the JMS API is that required to support durable subscriptions.

If another connection with the same clientID is already running when this method is called, the JMS provider should detect the duplicate ID and throw an InvalidClientIDException.

This method must not be used in a Java EE web or EJB application. Doing so may cause a JMSRuntimeException to be thrown though this is not guaranteed.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Parameters:

clientID - the unique client identifier

Throws:

InvalidClientIDRuntimeException - if the JMS client specifies an invalid or duplicate client ID.

IllegalStateRuntimeException -

• if the JMS client attempts to set the client ID for the JMSContext's connection at the wrong time or
• if the client ID has been administratively configured or
• if the JMSContext is container-managed (injected).

JMSRuntimeException - if the JMS provider fails to set the client ID for the the JMSContext's connection for one of the following reasons:

• an internal error has occurred or
• this method has been called in a Java EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)

getMetaData

ConnectionMetaData getMetaData()

Gets the connection metadata for the JMSContext's connection.

Returns:

the connection metadata

Throws:

JMSRuntimeException - if the JMS provider fails to get the connection metadata

See Also:

ConnectionMetaData

getExceptionListener

ExceptionListener getExceptionListener()

Gets the ExceptionListener object for the JMSContext's connection. Not every Connection has an ExceptionListener associated with it.

Returns:

the ExceptionListener for the JMSContext's connection, or null if no ExceptionListener is associated with that connection.

Throws:

JMSRuntimeException - if the JMS provider fails to get the ExceptionListener for the JMSContext's connection.

See Also:

Connection.setExceptionListener(javax.jms.ExceptionListener)

setExceptionListener

void setExceptionListener(ExceptionListener listener)

Sets an exception listener for the JMSContext's connection.

If a JMS provider detects a serious problem with a connection, it informs the connection's ExceptionListener, if one has been registered. It does this by calling the listener's onException method, passing it a JMSRuntimeException object describing the problem.

An exception listener allows a client to be notified of a problem asynchronously. Some connections only consume messages, so they would have no other way to learn their connection has failed.

A connection serializes execution of its ExceptionListener.

A JMS provider should attempt to resolve connection problems itself before it notifies the client of them.

This method must not be used in a Java EE web or EJB application. Doing so may cause a JMSRuntimeException to be thrown though this is not guaranteed.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Parameters:

listener - the exception listener

Throws:

IllegalStateRuntimeException - if the JMSContext is container-managed (injected).

JMSRuntimeException - if the JMS provider fails to set the exception listener for one of the following reasons:

• an internal error has occurred or
• this method has been called in a Java EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)

start

void start()

Starts (or restarts) delivery of incoming messages by the JMSContext's connection. A call to start on a connection that has already been started is ignored.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException - if the JMSContext is container-managed (injected).

JMSRuntimeException - if the JMS provider fails to start message delivery due to some internal error.

See Also:

stop()

stop

void stop()

Temporarily stops the delivery of incoming messages by the JMSContext's connection. Delivery can be restarted using the start method. When the connection is stopped, delivery to all the connection's message consumers is inhibited: synchronous receives block, and messages are not delivered to message listeners.

This call blocks until receives and/or message listeners in progress have completed.

Stopping a connection has no effect on its ability to send messages. A call to stop on a connection that has already been stopped is ignored.

A call to stop must not return until delivery of messages has paused. This means that a client can rely on the fact that none of its message listeners will be called and that all threads of control waiting for receive calls to return will not return with a message until the connection is restarted. The receive timers for a stopped connection continue to advance, so receives may time out while the connection is stopped.

If message listeners are running when stop is invoked, the stop call must wait until all of them have returned before it may return. While these message listeners are completing, they must have the full services of the connection available to them.

A message listener must not attempt to stop its own JMSContext as this would lead to deadlock. The JMS provider must detect this and throw a IllegalStateRuntimeException

For the avoidance of doubt, if an exception listener for the JMSContext's connection is running when stop is invoked, there is no requirement for the stop call to wait until the exception listener has returned before it may return.

This method must not be used in a Java EE web or EJB application. Doing so may cause a JMSRuntimeException to be thrown though this is not guaranteed.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException -

• if this method has been called by a MessageListener on its own JMSContext
• if the JMSContext is container-managed (injected).

JMSRuntimeException - if the JMS provider fails to stop message delivery for one of the following reasons:

• an internal error has occurred or
• this method has been called in a Java EE web or EJB application (though it is not guaranteed that an exception is thrown in this case)

See Also:

start()

setAutoStart

void setAutoStart(boolean autoStart)

Specifies whether the underlying connection used by this JMSContext will be started automatically when a consumer is created. This is the default behaviour, and it may be disabled by calling this method with a value of false.

This method does not itself either start or stop the connection.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Parameters:

autoStart - Whether the underlying connection used by this JMSContext will be automatically started when a consumer is created.

Throws:

IllegalStateRuntimeException - if the JMSContext is container-managed (injected)

See Also:

getAutoStart()

getAutoStart

boolean getAutoStart()

Returns whether the underlying connection used by this JMSContext will be started automatically when a consumer is created.

Returns:

whether the underlying connection used by this JMSContext will be started automatically when a consumer is created.

See Also:

setAutoStart(boolean)

close

void close()

Closes the JMSContext

This closes the underlying session and any underlying producers and consumers. If there are no other active (not closed) JMSContext objects using the underlying connection then this method also closes the underlying connection.

Since a provider typically allocates significant resources outside the JVM on behalf of a connection, clients should close these resources when they are not needed. Relying on garbage collection to eventually reclaim these resources may not be timely enough.

Closing a connection causes all temporary destinations to be deleted.

When this method is invoked, it should not return until message processing has been shut down in an orderly fashion. This means that all message listeners that may have been running have returned, and that all pending receives have returned. A close terminates all pending message receives on the connection's sessions' consumers. The receives may return with a message or with null, depending on whether there was a message available at the time of the close. If one or more of the connection's sessions' message listeners is processing a message at the time when connection close is invoked, all the facilities of the connection and its sessions must remain available to those listeners until they return control to the JMS provider.

This method must not return until any incomplete asynchronous send operations for this JMSContext 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 the JMSContext's connection is running when close is invoked, there is no requirement for the close call to wait until the exception listener has returned before it may return.

Closing a connection causes any of its sessions' transactions in progress to be rolled back. In the case where a session's work is coordinated by an external transaction manager, a session's commit and rollback methods are not used and the result of a closed session's work is determined later by the transaction manager.

Closing a connection does NOT force an acknowledgment of client-acknowledged sessions.

Invoking the acknowledge method of a received message from a closed connection's session must throw an IllegalStateRuntimeException. Closing a closed connection must NOT throw an exception.

A MessageListener must not attempt to close its own JMSContext as this would lead to deadlock. The JMS provider must detect this and throw a IllegalStateRuntimeException.

A CompletionListener callback method must not call close on its own JMSContext. Doing so will cause an IllegalStateRuntimeException to be thrown.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Specified by:

close in interface AutoCloseable

Throws:

IllegalStateRuntimeException -

• if this method has been called by a MessageListener on its own JMSContext
• if this method has been called by a CompletionListener callback method on its own JMSContext
• if the JMSContext is container-managed (injected)

JMSRuntimeException - if the JMS provider fails to close the JMSContext due to some internal error. For example, a failure to release resources or to close a socket connection can cause this exception to be thrown.

createBytesMessage

BytesMessage createBytesMessage()

Creates a BytesMessage object. A BytesMessage object is used to send a message containing a stream of uninterpreted bytes.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createMapMessage

MapMessage createMapMessage()

Creates a MapMessage object. A MapMessage object is used to send a self-defining set of name-value pairs, where names are String objects and values are primitive values in the Java programming language.

The message object returned may be sent using any Session or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createMessage

Message createMessage()

Creates a Message object. The Message interface is the root interface of all JMS messages. A Message 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 or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createObjectMessage

ObjectMessage createObjectMessage()

Creates an ObjectMessage object. An ObjectMessage object is used to send a message that contains a serializable Java object.

The message object returned may be sent using any Session or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createObjectMessage

ObjectMessage createObjectMessage(Serializable object)

Creates an initialized ObjectMessage object. An ObjectMessage object is used to send a message that contains a serializable Java object.

The message object returned may be sent using any Session or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Parameters:

object - the object to use to initialize this message

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createStreamMessage

StreamMessage createStreamMessage()

Creates a StreamMessage object. A StreamMessage 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 or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createTextMessage

TextMessage createTextMessage()

Creates a TextMessage object. A TextMessage object is used to send a message containing a String object.

The message object returned may be sent using any Session or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

createTextMessage

TextMessage createTextMessage(String text)

Creates an initialized TextMessage object. A TextMessage object is used to send a message containing a String.

The message object returned may be sent using any Session or JMSContext. It is not restricted to being sent using the JMSContext used to create it.

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.

Parameters:

text - the string used to initialize this message

Throws:

JMSRuntimeException - if the JMS provider fails to create this message due to some internal error.

getTransacted

boolean getTransacted()

Indicates whether the JMSContext's session is in transacted mode.

Returns:

true if the session is in transacted mode

Throws:

JMSRuntimeException - if the JMS provider fails to return the transaction mode due to some internal error.

getSessionMode

int getSessionMode()

Returns the session mode of the JMSContext's session. This can be set at the time that the JMSContext is created. Possible values are JMSContext.SESSION_TRANSACTED, JMSContext.AUTO_ACKNOWLEDGE, JMSContext.CLIENT_ACKNOWLEDGE and JMSContext.DUPS_OK_ACKNOWLEDGE

If a session mode was not specified when the JMSContext was created a value of JMSContext.AUTO_ACKNOWLEDGE will be returned.

Returns:

the session mode of the JMSContext's session

Throws:

JMSRuntimeException - if the JMS provider fails to return the acknowledgment mode due to some internal error.

Since:

JMS 2.0

See Also:

Connection.createSession(boolean, int)

commit

void commit()

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 JMSContext 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 JMSContext. Doing so will cause an IllegalStateRuntimeException to be thrown.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException -

• if the JMSContext's session is not using a local transaction
• if this method has been called by a CompletionListener callback method on its own JMSContext
• if the JMSContext is container-managed (injected)

TransactionRolledBackRuntimeException - if the transaction is rolled back due to some internal error during commit.

JMSRuntimeException - if the JMS provider fails to commit the transaction due to some internal error

rollback

void rollback()

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 JMSContext 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 rollback on its own JMSContext. Doing so will cause an IllegalStateRuntimeException to be thrown.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException -

• if the JMSContext's session is not using a local transaction
• if this method has been called by a CompletionListener callback method on its own JMSContext
• if the JMSContext is container-managed (injected)

JMSRuntimeException - if the JMS provider fails to roll back the transaction due to some internal error

recover

void recover()

Stops message delivery in the JMSContext's 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.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException -

• if the JMSContext's session is using a transaction
• if the JMSContext is container-managed (injected)

JMSRuntimeException - if the JMS provider fails to stop and restart message delivery due to some internal error

createConsumer

JMSConsumer createConsumer(Destination destination)

Creates a JMSConsumer for the specified destination.

A client uses a JMSConsumer object to receive messages that have been sent to a destination.

Parameters:

destination - the Destination to access.

Throws:

JMSRuntimeException - if the session fails to create a JMSConsumer due to some internal error.

InvalidDestinationRuntimeException - if an invalid destination is specified.

createConsumer

JMSConsumer createConsumer(Destination destination,
                           String messageSelector)

Creates a JMSConsumer for the specified destination, using a message selector.

A client uses a JMSConsumer object to receive messages that have been sent to a destination.

Parameters:

destination - the Destination to access

messageSelector - only messages with properties matching the message selector expression are delivered. A value of null or an empty string indicates that there is no message selector for the JMSConsumer.

Throws:

JMSRuntimeException - if the session fails to create a JMSConsumer due to some internal error.

InvalidDestinationRuntimeException - if an invalid destination is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

createConsumer

JMSConsumer createConsumer(Destination destination,
                           String messageSelector,
                           boolean noLocal)

Creates a JMSConsumer for the specified destination, specifying a message selector and the noLocal parameter.

A client uses a JMSConsumer object to receive messages that have been sent to a destination.

The noLocal argument is for use when the destination is a topic and the JMSContext's connection is also being used to publish messages to that topic. If noLocal is set to true then the JMSConsumer 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 setting noLocal to true is not specified.

Parameters:

destination - the Destination to access

messageSelector - only messages with properties matching the message selector expression are delivered. A value of null or an empty string indicates that there is no message selector for the JMSConsumer.

noLocal - if true, and the destination is a topic, then the JMSConsumer will not receive messages published to the topic by its own connection

Throws:

JMSRuntimeException - if the session fails to create a JMSConsumer due to some internal error.

InvalidDestinationRuntimeException - if an invalid destination is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

createQueue

Queue createQueue(String queueName)

Creates a Queue 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 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 createTemporaryQueue method.

Parameters:

queueName - A provider-specific queue name

Returns:

a Queue object which encapsulates the specified name

Throws:

JMSRuntimeException - if a Queue object cannot be created due to some internal error

createTopic

Topic createTopic(String topicName)

Creates a Topic 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 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 createTemporaryTopic method.

Parameters:

topicName - A provider-specific topic name

Returns:

a Topic object which encapsulates the specified name

Throws:

JMSRuntimeException - if a Topic object cannot be created due to some internal error

createDurableConsumer

JMSConsumer 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. This method creates the durable subscription without a message selector and with a noLocal value of false.

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 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 or JMSConsumer 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 a JMSConsumer 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 JMSRuntimeException 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 JMSRuntimeException 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.

Parameters:

topic - the non-temporary Topic to subscribe to

name - the name used to identify this subscription

Throws:

InvalidDestinationRuntimeException - if an invalid topic is specified.

IllegalStateRuntimeException - if the client identifier is unset

JMSRuntimeException -

• if the session fails to create the non-shared durable subscription and JMSConsumer 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

Since:

JMS 2.0

createDurableConsumer

JMSConsumer 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 the noLocal 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 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 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 or JMSConsumer 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 a JMSConsumer 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 JMSRuntimeException 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 JMSContext'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 JMSRuntimeException 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 a MessageConsumer rather than a TopicSubscriber to represent the consumer.

Parameters:

topic - the non-temporary Topic to subscribe to

name - the name used to identify this subscription

messageSelector - 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.

Throws:

InvalidDestinationRuntimeException - if an invalid topic is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

IllegalStateRuntimeException - if the client identifier is unset

JMSRuntimeException -

• if the session fails to create the non-shared durable subscription and JMSConsumer 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

Since:

JMS 2.0

createSharedDurableConsumer

JMSConsumer 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 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 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 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 or JMSConsumer 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 JMSConsumer 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 JMSRuntimeException 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 JMSRuntimeException is thrown.

If a message selector is specified then only messages with properties matching the message selector expression will be added to the subscription.

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-temporary Topic to subscribe to

name - the name used to identify this subscription

Throws:

InvalidDestinationRuntimeException - if an invalid topic is specified.

JMSRuntimeException -

• 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

Since:

JMS 2.0

createSharedDurableConsumer

JMSConsumer 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.

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 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 or JMSConsumer 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 have been specified, then this method creates a JMSConsumer 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 JMSRuntimeException 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 JMSRuntimeException 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-temporary Topic to subscribe to

name - the name used to identify this subscription

messageSelector - 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.

Throws:

InvalidDestinationRuntimeException - if an invalid topic is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

JMSRuntimeException -

• if the session fails to create the shared durable subscription and JMSConsumer 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

Since:

JMS 2.0

createSharedConsumer

JMSConsumer 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. 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 has been specified, then this method creates a JMSConsumer 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 or JMSConsumer 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 value has been specified, and there is a consumer already active (i.e. not closed) on the subscription, then a JMSRuntimeException 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 - the Topic to subscribe to

sharedSubscriptionName - the name used to identify the shared non-durable subscription

Throws:

JMSRuntimeException - if the session fails to create the shared non-durable subscription and JMSContext due to some internal error.

InvalidDestinationRuntimeException - if an invalid topic is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

createSharedConsumer

JMSConsumer 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.

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 JMSConsumer 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 or JMSConsumer 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 JMSRuntimeException 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 - the Topic to subscribe to

sharedSubscriptionName - the name used to identify the shared non-durable subscription

messageSelector - 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.

Throws:

JMSRuntimeException - if the session fails to create the shared non-durable subscription and JMSConsumer due to some internal error.

InvalidDestinationRuntimeException - if an invalid topic is specified.

InvalidSelectorRuntimeException - if the message selector is invalid.

createBrowser

QueueBrowser createBrowser(Queue queue)

Creates a QueueBrowser object to peek at the messages on the specified queue.

Parameters:

queue - the queue to access

Throws:

JMSRuntimeException - if the session fails to create a browser due to some internal error.

InvalidRuntimeDestinationException - if an invalid destination is specified

createBrowser

QueueBrowser createBrowser(Queue queue,
                           String messageSelector)

Creates a QueueBrowser object to peek at the messages on the specified queue using a message selector.

Parameters:

queue - the queue to access

messageSelector - only messages with properties matching the message selector expression are delivered. A value of null or an empty string indicates that there is no message selector for the message consumer.

Throws:

JMSRuntimeException - if the session fails to create a browser due to some internal error.

InvalidRuntimeDestinationException - if an invalid destination is specified

InvalidRuntimeSelectorException - if the message selector is invalid.

createTemporaryQueue

TemporaryQueue createTemporaryQueue()

Creates a TemporaryQueue object. Its lifetime will be that of the JMSContext's Connection unless it is deleted earlier.

Returns:

a temporary queue identity

Throws:

JMSRuntimeException - if the session fails to create a temporary queue due to some internal error.

createTemporaryTopic

TemporaryTopic createTemporaryTopic()

Creates a TemporaryTopic object. Its lifetime will be that of the JMSContext's Connection unless it is deleted earlier.

Returns:

a temporary topic identity

Throws:

JMSRuntimeException - if the session fails to create a temporary topic due to some internal error.

unsubscribe

void unsubscribe(String name)

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 on that subscription, or while a consumed message is part of a pending transaction or has not been acknowledged in the session.

If the active consumer is represented by a JMSConsumer then calling close on either that object or the JMSContext used to create it will render the consumer inactive and allow the subscription to be deleted.

If the active consumer was created by calling setMessageListener on the JMSContext then calling close on the JMSContext will render the consumer inactive and allow the subscription to be deleted.

If the active consumer is represented by a MessageConsumer or TopicSubscriber then calling close on that object or on the Session or Connection used to create it will render the consumer inactive and allow the subscription to be deleted.

Parameters:

name - the name used to identify this subscription

Throws:

JMSRuntimeException - if the session fails to unsubscribe to the durable subscription due to some internal error.

InvalidDestinationRuntimeException - if an invalid subscription name is specified.

acknowledge

void acknowledge()

Acknowledges all messages consumed by the JMSContext's session.

This method is for use when the session has an acknowledgement mode of CLIENT_ACKNOWLEDGE. If the session is transacted or has an acknowledgement mode of AUTO_ACKNOWLEDGE or DUPS_OK_ACKNOWLEDGE calling this method has no effect.

This method has identical behaviour to the acknowledge method on Message. A client may individually acknowledge each message as it is consumed, or it may choose to acknowledge messages as an application-defined group. In both cases it makes no difference which of these two methods is used.

Messages that have been received but not acknowledged may be redelivered.

This method must not be used if the JMSContext is container-managed (injected). Doing so will cause a IllegalStateRuntimeException to be thrown.

Throws:

IllegalStateRuntimeException -

• if the JMSContext is closed.
• if the JMSContext is container-managed (injected)

JMSRuntimeException - if the JMS provider fails to acknowledge the messages due to some internal error

See Also:

Session.CLIENT_ACKNOWLEDGE, Message.acknowledge()