Module jakarta.messaging

Package jakarta.jms

The Jakarta Messaging API provides a common way for Java programs to create, send, receive and read an enterprise messaging system's messages.

Jakarta Messaging Applications

A Jakarta Messaging application is composed of the following parts:

• Jakarta Messaging provider - a messaging system that implements the Jakarta Messaging API in addition to the other administrative and control functionality required of a full-featured messaging product
• Jakarta Messaging clients - the Java language programs that send and receive messages
• Messages - objects that are used to communicate information between the clients of an application
• Administered objects - provider-specific objects that clients look up and use to interact portably with a Jakarta Messaging provider
• Non-Jakarta Messaging clients - clients that use a message system's native client API instead of the Jakarta Messaging API. If the application predated the availability of the Jakarta Messaging API, it is likely that it will include both Jakarta Messaging clients and non-Jakarta Messaging clients.

Administration

Jakarta Messaging providers differ significantly in their implementations of underlying messaging technology. There are also major differences in how a Jakarta Messaging provider's system is installed and administered.

For Jakarta Messaging clients to be portable, they must be isolated from these proprietary aspects of a provider. This is done by defining Jakarta Messaging administered objects that are created and customised by a provider's administrator and later used by clients. The client uses them through Jakarta Messaging interfaces that are portable. The administrator creates them using provider-specific facilities.

There are two types of Jakarta Messaging administered objects:

• ConnectionFactory - the object a client uses to create a connection with a Jakarta Messaging provider
• Destination - the object a client uses to specify the destination of messages it is sending and the source of messages it receives

Administered objects are placed by an administrator in a JNDI (Java Naming and Directory Interface) namespace. A Jakarta Messaging client typically notes in its documentation the Jakarta Messaging administered objects it requires and how the JNDI names of these objects should be provided to it.

Two Messaging Styles

Jakarta Messaging supports two styles of messaging:

• point-to-point (PTP) messaging using queues
• publish-and-subscribe (pub/sub)messaging using topics

These two styles represent two of the dominant approaches to messaging currently in use.

Jakarta Messaging APIs

For historical reasons Jakarta Messaging offers four alternative sets of interfaces for sending and receiving messages:

• Java Message Service 1.0 defined two domain-specific APIs, one for point-to-point messaging (queues) and one for pub/sub (topics). Although these remain part of Jakarta Messaging for reasons of backwards compatibility they should be considered to be completely superseded by the later APIs.
• Java Message Service 1.1 introduced a new unified API which offered a single set of interfaces that could be used for both point-to-point and pub/sub messaging. This is referred to here as the classic API.
• Jakarta Messaging 2.0 introduces a simplified API which offers all the features of the classic API but which requires fewer interfaces and is simpler to use.

Each API offers a different set of interfaces for connecting to a Jakarta Messaging provider and for sending and receiving messages. However they all share a common set of interfaces for representing messages and message destinations and to provide various utility features.

All interfaces are in the jakarta.jms package.

Interfaces common to multiple APIs

The main interfaces common to multiple APIs are as follows:

• Message, BytesMessage, MapMessage, ObjectMessage, StreamMessage and TextMessage - a message sent to or received from a Jakarta Messaging provider.
• Queue - an administered object that encapsulates the identity of a message destination for point-to-point messaging
• Topic - an administered object that encapsulates the identity of a message destination for pub/sub messaging.
• Destination - the common supertype of Queue and Topic

Classic API interfaces

The main interfaces provided by the classic API are as follows:

• ConnectionFactory - an administered object used by a client to create a Connection. This interface is also used by the simplified API.
• Connection - an active connection to a Jakarta Messaging provider
• Session - a single-threaded context for sending and receiving messages
• MessageProducer - an object created by a Session that is used for sending messages to a queue or topic
• MessageConsumer - an object created by a Session that is used for receiving messages sent to a queue or topic

Simplified API interfaces

The simplified API provides the same messaging functionality as the classic API but requires fewer interfaces and is simpler to use. The main interfaces provided by the simplified API are as follows:

• ConnectionFactory - an administered object used by a client to create a JMSContext. This interface is also used by the classic API.
• JMSContext - an active connection to a Jakarta Messaging provider and a single-threaded context for sending and receiving messages
• JMSProducer - an object created by a JMSContext that is used for sending messages to a queue or topic
• JMSConsumer - an object created by a JMSContext that is used for receiving messages sent to a queue or topic

Legacy domain-specific API interfaces

Although the domain-specific API remains part of Jakarta Messaging for reasons of backwards compatibility it should be considered to be completely superseded by the classic and simplified APIs.

The main interfaces provided by the domain-specific API for point-to-point messaging are as follows:

• QueueConnectionFactory - an administered object used by a client to create a QueueConnection.
• QueueConnection - an active connection to a Jakarta Messaging provider
• QueueSession - a single-threaded context for sending and receiving messages
• QueueSender - an object created by a QueueSession that is used for sending messages to a queue
• QueueReceiver - an object created by a QueueSession that is used for receiving messages sent to a queue

The main interfaces provided by the domain-specific API for pub/sub messaging are as follows:

• TopicConnectionFactory - an administered object used by a client to create a TopicConnection.
• TopicConnection - an active connection to a Jakarta Messaging provider
• TopicSession - a single-threaded context for sending and receiving messages
• TopicPublisher - an object created by a TopicSession that is used for sending messages to a topic
• TopicSubscriber - an object created by a TopicSession that is used for receiving messages sent to a topic

Terminology for sending and receiving messages

The term consume is used in this document to mean the receipt of a message by a Jakarta Messaging client; that is, a Jakarta Messaging provider has received a message and has given it to its client. Since Jakarta Messaging supports both synchronous and asynchronous receipt of messages, the term consume is used when there is no need to make a distinction between them.

The term produce is used as the most general term for sending a message. It means giving a message to a Jakarta Messaging provider for delivery to a destination.

Developing a Jakarta Messaging Application

Broadly speaking, a Jakarta Messaging application is one or more Jakarta Messaging clients that exchange messages. The application may also involve non-Jakarta Messaging clients; however, these clients use the Jakarta Messaging provider's native API in place of the Jakarta Messaging API.

A Jakarta Messaging application can be architected and deployed as a unit. In many cases, Jakarta Messaging clients are added incrementally to an existing application.

The message definitions used by an application may originate with JMS, or they may have been defined by the non-Jakarta Messaging part of the application.

Developing a Jakarta Messaging Client

A typical Jakarta Messaging client using the classic API executes the following Jakarta Messaging setup procedure:

• Use JNDI to find a ConnectionFactory object
• Use JNDI to find one or more Destination objects
• Use the ConnectionFactory to create a Jakarta Messaging Connection object with message delivery inhibited
• Use the Connection to create one or more Jakarta Messaging Session objects
• Use a Session and the Destinations to create the MessageProducer and MessageConsumer objects needed
• Tell the Connection to start delivery of messages

In contrast, a typical Jakarta Messaging client using the simplified API does the following:

• Use JNDI to find a ConnectionFactory object
• Use JNDI to find one or more Destination objects
• Use the ConnectionFactory to create a JMSContext object
• Use the JMSContext to create the JMSProducer and JMSConsumer objects needed.
• Delivery of message is started automatically

At this point a client has the basic Jakarta Messaging setup needed to produce and consume messages.

Package Specification

Jakarta Messaging 3.1 specification

Related Documentation

Jakarta Enterprise Edition Technical Documentation

Interface Summary

Interface	Description
BytesMessage	A BytesMessage object is used to send a message containing a stream of uninterpreted bytes.
CompletionListener	A CompletionListener is implemented by the application and may be specified when a message is sent asynchronously.
Connection	A Connection object is a client's active connection to its Jakarta Messaging provider.
ConnectionConsumer	For application servers, Connection objects provide a special facility for creating a ConnectionConsumer (optional).
ConnectionFactory	A ConnectionFactory object encapsulates a set of connection configuration parameters that has been defined by an administrator.
ConnectionMetaData	A ConnectionMetaData object provides information describing the Connection object.
DeliveryMode	The delivery modes supported by the Jakarta Messaging API are PERSISTENT and NON_PERSISTENT.
Destination	A Destination object encapsulates a provider-specific address.
ExceptionListener	If a Jakarta Messaging provider detects a serious problem with a Connection object, it informs the Connection object's ExceptionListener, if one has been registered.
JMSConsumer	A client using the simplified Jakarta Messaging API introduced for Jakarta Messaging 2.0 uses a JMSConsumer object to receive messages from a queue or topic.
JMSContext	A JMSContext is the main interface in the simplified Jakarta Messaging API introduced for Jakarta Messaging 2.0.
JMSProducer	A JMSProducer is a simple object used to send messages on behalf of a JMSContext.
MapMessage	A MapMessage object is used to send a set of name-value pairs.
Message	The Message interface is the root interface of all Jakarta Messaging messages.
MessageConsumer	A client uses a MessageConsumer object to receive messages from a destination.
MessageListener	A MessageListener object is used to receive asynchronously delivered messages.
MessageProducer	A client uses a MessageProducer object to send messages to a destination.
ObjectMessage	An ObjectMessage object is used to send a message that contains a serializable object in the Java programming language ("Java object").
Queue	A Queue object encapsulates a provider-specific queue name.
QueueBrowser	A client uses a QueueBrowser object to look at messages on a queue without removing them.
QueueConnection	A QueueConnection object is an active connection to a point-to-point Jakarta Messaging provider.
QueueConnectionFactory	A client uses a QueueConnectionFactory object to create QueueConnection objects with a point-to-point Jakarta Messaging provider.
QueueReceiver	A client uses a QueueReceiver object to receive messages that have been delivered to a queue.
QueueSender	A client uses a QueueSender object to send messages to a queue.
QueueSession	A QueueSession object provides methods for creating QueueReceiver, QueueSender, QueueBrowser, and TemporaryQueue objects.
ServerSession	A ServerSession object is an application server object that is used by a server to associate a thread with a Jakarta Messaging session (optional).
ServerSessionPool	A ServerSessionPool object is an object implemented by an application server to provide a pool of ServerSession objects for processing the messages of a ConnectionConsumer (optional).
Session	A Session object is a single-threaded context for producing and consuming messages.
StreamMessage	A StreamMessage object is used to send a stream of primitive types in the Java programming language.
TemporaryQueue	A TemporaryQueue object is a unique Queue object created for the duration of a Connection.
TemporaryTopic	A TemporaryTopic object is a unique Topic object created for the duration of a Connection.
TextMessage	A TextMessage object is used to send a message containing a java.lang.String.
Topic	A Topic object encapsulates a provider-specific topic name.
TopicConnection	A TopicConnection object is an active connection to a publish/subscribe Jakarta Messaging provider.
TopicConnectionFactory	A client uses a TopicConnectionFactory object to create TopicConnection objects with a publish/subscribe Jakarta Messaging provider.
TopicPublisher	A client uses a TopicPublisher object to publish messages on a topic.
TopicSession	A TopicSession object provides methods for creating TopicPublisher, TopicSubscriber, and TemporaryTopic objects.
TopicSubscriber	A client uses a TopicSubscriber object to receive messages that have been published to a topic.
XAConnection	The XAConnection interface extends the capability of Connection by providing an XASession (optional).
XAConnectionFactory	The XAConnectionFactory interface is a base interface for the XAQueueConnectionFactory and XATopicConnectionFactory interfaces.
XAJMSContext	The XAJMSContext interface extends the capability of JMSContext by adding access to a Jakarta Messaging provider's support for the Java Transaction API (JTA) (optional).
XAQueueConnection	An XAQueueConnection provides the same create options as QueueConnection (optional).
XAQueueConnectionFactory	An XAQueueConnectionFactory provides the same create options as a QueueConnectionFactory (optional).
XAQueueSession	An XAQueueSession provides a regular QueueSession, which can be used to create QueueReceiver, QueueSender, and QueueBrowser objects (optional).
XASession	The XASession interface extends the capability of Session by adding access to a Jakarta Messaging provider's support for the Java Transaction API (JTA) (optional).
XATopicConnection	An XATopicConnection provides the same create options as TopicConnection (optional).
XATopicConnectionFactory	An XATopicConnectionFactory provides the same create options as a TopicConnectionFactory (optional).
XATopicSession	An XATopicSession provides a regular TopicSession.

Class Summary

Class	Description
QueueRequestor	The QueueRequestor helper class simplifies making service requests.
TopicRequestor	The TopicRequestor helper class simplifies making service requests.

Exception Summary

Exception	Description
IllegalStateException	This exception is thrown when a method is invoked at an illegal or inappropriate time or if the provider is not in an appropriate state for the requested operation.
IllegalStateRuntimeException	This unchecked exception is thrown when a method is invoked at an illegal or inappropriate time or if the provider is not in an appropriate state for the requested operation, and the method signature does not permit a IllegalStateRuntimeException to be thrown.
InvalidClientIDException	This exception must be thrown when a client attempts to set a connection's client ID to a value that is rejected by a provider.
InvalidClientIDRuntimeException	This unchecked exception must be thrown when a client attempts to set a connection's client ID to a value that is rejected by a provider, and the method signature does not permit a InvalidClientIDException to be thrown.
InvalidDestinationException	This exception must be thrown when a destination either is not understood by a provider or is no longer valid.
InvalidDestinationRuntimeException	This unchecked exception must be thrown when a destination either is not understood by a provider or is no longer valid, and the method signature does not permit a InvalidDestinationException to be thrown.
InvalidSelectorException	This exception must be thrown when a Jakarta Messaging client attempts to give a provider a message selector with invalid syntax.
InvalidSelectorRuntimeException	This unchecked exception must be thrown when a Jakarta Messaging client attempts to give a provider a message selector with invalid syntax, and the method signature does not permit a InvalidSelectorException to be thrown.
JMSException	This is the root class of all checked exceptions in the Jakarta Messaging API.
JMSRuntimeException	This is the root class of all unchecked exceptions in the Jakarta Messaging API.
JMSSecurityException	This exception must be thrown when a provider rejects a user name/password submitted by a client.
JMSSecurityRuntimeException	This unchecked exception must be thrown when a provider rejects a user name/password submitted by a client, or for any case where a security restriction prevents a method from completing, and the method signature does not permit a JMSSecurityException to be thrown.
MessageEOFException	This exception must be thrown when an unexpected end of stream has been reached when a StreamMessage or BytesMessage is being read.
MessageFormatException	This exception must be thrown when a Jakarta Messaging client attempts to use a data type not supported by a message or attempts to read data in a message as the wrong type.
MessageFormatRuntimeException	This unchecked exception must be thrown when a Jakarta Messaging application attempts to use a data type not supported by a message or attempts to read data in a message as the wrong type, and the method signature does not permit a MessageFormatException to be thrown.
MessageNotReadableException	This exception must be thrown when a Jakarta Messaging client attempts to read a write-only message.
MessageNotWriteableException	This exception must be thrown when a Jakarta Messaging client attempts to write to a read-only message.
MessageNotWriteableRuntimeException	This unchecked exception must be thrown when a Jakarta Messaging client attempts to write to a read-only message.
ResourceAllocationException	This exception is thrown when a provider is unable to allocate the resources required by a method.
ResourceAllocationRuntimeException	This unchecked exception is thrown when a provider is unable to allocate the resources required by a method.
TransactionInProgressException	This exception is thrown when an operation is invalid because a transaction is in progress.
TransactionInProgressRuntimeException	This unchecked exception is thrown when an operation is invalid because a transaction is in progress.
TransactionRolledBackException	This exception must be thrown when a call to Session.commit results in a rollback of the current transaction.
TransactionRolledBackRuntimeException	This unchecked exception must be thrown when a call to JMSContext.commit results in a rollback of the current transaction.

Annotation Types Summary

Annotation Type	Description
JMSConnectionFactory	This annotation may be used on a field to specify the JNDI lookup name of a jakarta.jms.ConnectionFactory to be used when injecting a jakarta.jms.JMSContext object.
JMSConnectionFactoryDefinition	An application may use this annotation to specify a Jakarta Messaging ConnectionFactory resource that it requires in its operational environment.
JMSConnectionFactoryDefinitions	Specifies one or more JMSConnectionFactoryDefinition annotations.
JMSDestinationDefinition	An application may use this annotation to specify a Jakarta Messaging Destination resource that it requires in its operational environment.
JMSDestinationDefinitions	Specifies one or more JMSDestinationDefinition annotations.
JMSPasswordCredential	This annotation may be used to specify the userName and password to be used when injecting a jakarta.jms.JMSContext object.
JMSSessionMode	This annotation may be used to specify the session mode to be used when injecting a jakarta.jms.JMSContext object.