Using the Java Message Service (JMS)

CXF provides a transport plug-in that enables endpoints to use Java Message Service (JMS) queues and topics. CXF's JMS transport plug-in uses the Java Naming and Directory Interface (JNDI) to locate and obtain references to the JMS provider that brokers for the JMS destinations. Once CXF has established a connection to a JMS provider, CXF supports the passing of messages packaged as either a JMS ObjectMessage or a JMS TextMessage. The JMS transport also supports the SOAP over JMS specification. See SOAP over JMS 1.0 support for more information.

Standard JMS transport configuration in CXF is done by defining a JMSConduit or JMSDestination, discussed below. There is however an easier configuration option more conformant to Spring dependency injection, see Using the JMSConfigFeature.

JMS Namespaces

WSDL Namespace

The WSDL extensions for defining a JMS endpoint are defined in the namespace http://cxf.apache.org/transports/jms. In order to use the JMS extensions you will need to add the namespace definition shown below to the definitions element of your contract.

JMS Extension Namespace

Configuration Namespaces

In order to use the JMS configuration properties you will need to add the line shown below to the beans element of your configuration.

JMS Configuration Namespaces

Basic Endpoint Configuration

JMS endpoints need to know certain basic information about how to establish a connection to the proper destination. This information can be provided in one of two places: WSDL or XML configuration. The following configuration elements which are described can be used in both the client side Conduits and the server side Destinations.

Using WSDL

The JMS destination information is provided using the jms:address element and its child, the jms:JMSNamingProperties element. The jms:address element's attributes specify the information needed to identify the JMS broker and the destination. The jms:JMSNamingProperties element specifies the Java properties used to connect to the JNDI service.

The address element

The basic configuration for a JMS endpoint is done by using a jms:address element as the child of your service's port element. The jms:address element uses the attributes described below to configure the connection to the JMS broker.

Attribute

Description

destinationStyle

Specifies if the JMS destination is a JMS queue or a JMS topic.

jndiConnectionFactoryName

Specifies the JNDI name bound to the JMS connection factory to use when connecting to the JMS destination.

jndiDestinationName

Specifies the JNDI name bound to the JMS destination to which requests are sent.

jndiReplyDestinationName

Specifies the JNDI name bound to the JMS destinations where replies are sent. This attribute allows you to use a user defined destination for replies.

connectionUserName

Specifies the username to use when connecting to a JMS broker.

connectionPassword

Specifies the password to use when connecting to a JMS broker.

The JMSNamingProperties element

To increase interoperability with JMS and JNDI providers, the jms:address element has a child element, jms:JMSNamingProperties, that allows you to specify the values used to populate the properties used when connecting to the JNDI provider. The jms:JMSNamingProperties element has two attributes: name and value. The name attribute specifies the name of the property to set. The value attribute specifies the value for the specified property. The jms:JMSNamingProperties element can also be used for specification of provider specific properties.
The following is a list of common JNDI properties that can be set:

  1. java.naming.factory.initial
  2. java.naming.provider.url
  3. java.naming.factory.object
  4. java.naming.factory.state
  5. java.naming.factory.url.pkgs
  6. java.naming.dns.url
  7. java.naming.authoritative
  8. java.naming.batchsize
  9. java.naming.referral
  10. java.naming.security.protocol
  11. java.naming.security.authentication
  12. java.naming.security.principal
  13. java.naming.security.credentials
  14. java.naming.language
  15. java.naming.applet

For more details on what information to use in these attributes, check your JNDI provider's documentation and consult the Java API reference material.

Using a named reply destination

By default, CXF endpoints using JMS create a temporary queue for sending replies back and forth. You can change this behavior by setting the jndiReplyDestinationName attribute in the endpoint's contract. A client endpoint will listen for replies on the specified destination and it will specify the value of the attribute in the ReplyTo field of all outgoing requests. A service endpoint will use the value of the jndiReplyDestinationName attribute as the location for placing replies if there is no destination specified in the request's ReplyTo field.

A static reply queue can not be shared by several instances of the service client. Please use a dynamic reply queue or different queue names per instance instead.

The following example shows an example of a JMS WSDL port specification.

JMS WSDL Port Specification

Using Configuration

In addition to using the WSDL file to specify the connection information for a JMS endpoint, you can also supply it in the endpoint's XML configuration. The information in the configuration file will override the information in the endpoint's WSDL file.

Configuration elements

You configure a JMS endpoint using one of the following configuration elements:

  • jms:conduit: The jms:conduit element contains the configuration for a consumer endpoint. It has one attribute, name, whose value takes the form
    {WSDLNamespace}WSDLPortName.jms-conduit
    
    .
  • jms:destination: The jms:destination element contains the configuration for a provider endpoint. It has one attribute, name, whose value takes the form
    {WSDLNamespace}WSDLPortName.jms-destination
    
    .

The address element

JMS connection information is specified by adding a jms:address child to the base configuration element. The jms:address element used in the configuration file is identical to the one used in the WSDL file. Its attributes are listed in the address element's attribute table. Like the jms:address element in the WSDL file, the jms:address configuration element also has a jms:JMSNamingProperties child element that is used to specify additional information used to connect to a JNDI provider.

Example

Addressing Information a Configuration File

Consumer Endpoint Configuration

JMS consumer endpoints specify the type of messages they use. JMS consumer endpoint can use either a JMS ObjectMessage or a JMS TextMessage. When using an ObjectMessage the consumer endpoint uses a byte[] as the method for storing data into and retrieving data from the JMS message body. When messages are sent, the message data, including any formating information, is packaged into a byte[] and placed into the JMS message body before it is placed on the wire. When messages are received, the consumer endpoint will attempt to unmarshall the data stored in the JMS body as if it were packed in a byte[].

When using a TextMessage, the consumer endpoint uses a string as the method for storing and retrieving data from the JMS message body. When messages are sent, the message information, including any format-specific information, is converted into a string and placed into the JMS message body. When messages are received the consumer endpoint will attempt to unmashall the data stored in the JMS message body as if it were packed into a string.

When native JMS applications interact with CXF consumers, the JMS application is responsible for interpreting the message and the formatting information. For example, if the CXF contract specifies that the binding used for a JMS endpoint is SOAP, and the messages are packaged as TextMessage, the receiving JMS application will get a text message containing all of the SOAP envelope information.

Consumer endpoint can be configured by both XML configuration and via WSDL.

Using Configuration

Specifying the message type

You can specify the message type supported by the consumer endpoint using a jms:runtimePolicy element that has a single attribute:

  • messageType - Specifies how the message data will be packaged as a JMS message. text specifies that the data will be packaged as a TextMessage. binary specifies that the data will be packaged as an ObjectMessage.

The following example shows a configuration entry for configuring a JMS consumer endpoint.

Configuration for a JMS Consumer Endpoint

The id on the jms:conduit is in the form of {WSDLNamespace}WSDLPortName.jms-conduit. This provides CXF with the information so that it can associate the configuration with your service's endpoint.

Using WSDL

The type of messages accepted by a JMS consumer endpoint is configured using the optional jms:client element. The jms:client element is a child of the WSDL port element and has one attribute:

  • messageType - Specifies how the message data will be packaged as a JMS message. text specifies that the data will be packaged as a TextMessage. binary specifies that the data will be packaged as an ObjectMessage.

Service Endpoint Configuration

JMS service endpoints have a number of behaviors that are configurable in the contract. These include:

  • how messages are correlated
  • the use of durable subscriptions
  • if the service uses local JMS transactions
  • the message selectors used by the endpoint

Service endpoints can be configure in one of two ways:

  • Configuration
  • WSDL

Using Configuration

Specifying configuration data

Using the jms:destination elements you can configure your service's endpoint. You can specify the service endpoint's behaviors using the jms:runtimePolicy element that has a the following attributes:

Attribute

Description

useMessageIDAsCorrealationID

Specifies whether the JMS broker will use the message ID to correlate messages. The default is false.

durableSubscriberName

Specifies the name used to register a durable subscription.

messageSelector

Specifies the string value of a message selector to use. For more information on the syntax used to specify message
selectors, see the JMS 1.1 specification.

transactional

Specifies whether the local JMS broker will create transactions around message processing. The default is false.

The following example shows a CXF configuration entry for configuring a JMS service endpoint.

Configuration for a JMS Service Endpoint

Using WSDL

Service endpoint behaviors are configured using the optional jms:server element. The jms:server element is a child of the WSDL port element and has the following attributes:

Attribute

Description

useMessageIDAsCorrealationID

Specifies whether JMS will use the message ID to correlate messages. The default is false.

durableSubscriberName

Specifies the name used to register a durable subscription.

messageSelector

Specifies the string value of a message selector to use. For more information on the syntax used to specify message
selectors, see the JMS 1.1 specification.

transactional

Specifies whether the local JMS broker will create transactions around message processing. The default is false. Currently, this is not supported by the runtime.

JMS Runtime Configuration

In addition to configuring the externally visible aspects of your JMS endpoint, you can also configure aspects of its internal runtime behavior. There are three types of runtime configuration:

  • Session pool configuration (common to both services and consumers)
  • Consumer specific configuration
  • Service specific configuration

Session Pool Configuration

You configure an endpoint's JMS session pool using the jms:sessionPoolConfig element. This property allows you to set a high and low water mark for the number of JMS sessions an endpoint will keep pooled. The endpoint is guaranteed to maintain a pool of sessions equal to the low water mark and to never pool more sessions than specified by the high water mark.
The jms:sessionPool element's attributes, listed below, specify the high and low water marks for the endpoint's JMS session pool.

Attribute

Description

lowWaterMark

Specifies the minimum number of JMS sessions pooled by the endpoint. The default is 20.

highWaterMark

Specifies the maximum number of JMS sessions pooled by the endpoint. The default is 500.

The following example shows an example of configuring the session pool for a CXF JMS service endpoint.

JMS Session Pool Configuration

The jms:sessionPool element can also be used within a jms:conduit.

Consumer Specific Runtime Configuration

The JMS consumer configuration allows you to specify two runtime behaviors:

  • the number of milliseconds the consumer will wait for a response.
  • the number of milliseconds a request will exist before the JMS broker can remove it.

You use the jms:clientConfig element to set JMS consumer runtime behavior. This element's attributes, listed in the following table, specify the configuration values for consumer runtime behavior.

Attribute

Description

clientReceiveTimeout

Specifies the amount of time, in milliseconds, that the endpoint will wait for a response before it times out and issues an exception. The default value is 2000.

messageTimeToLive

Specifies the amount of time, in milliseconds, that a request can remain unrecieved before the JMS broker can delete it. The default value is 0 which specifies that the message can never be deleted.

The following example shows a configuration fragment that sets the consumer endpoint's request lifetime to 500 milliseconds and its timeout value to 500 milliseconds.

JMS Consumer Endpoint Runtime Configuration

Service Specific Runtime Configuration

The JMS service configuration allows you to specify to runtime behaviors:

  • the amount of time a response message can remain unreceived before the JMS broker can delete it.
  • the client identifier used when creating and accessing durable subscriptions.

The jms:serverConfig element is used to specify the service runtime configuration. This element's attributes, listed below, specify the configuration values that control the service's runtime behavior.

Attribute

Description

messageTimeToLive

Specifies the amount of time, in milliseconds, that a response can remain unread before the JMS broker is allowed to delete it. The default is 0 which specifies that the message can live forever.

durableSubscriptionClientId

Specifies the client identifier the endpoint uses to create and access durable subscriptions.

The following example shows a configuration fragment that sets the service endpoint's response lifetime to 500 milliseconds and its durable subscription client identifier to jms-test-id.

JMS Service Endpoint Runtime Configuration