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Chapter 13. Introduction to the Red Hat JBoss Fuse JMS Binding Component

Abstract

The JMS binding component allows you to create endpoints that interact with JMS destinations outside of the Red Hat JBoss Fuse's runtime environment. It provides a robust and highly configurable means to interact with JMS systems.
Important
The Java Business Integration components of Red Hat JBoss Fuse are considered deprecated. You should consider migrating any JBI applications to OSGi.

Overview

The Red Hat JBoss Fuse JMS binding component is built using the Spring 2.0 JMS framework. It allows you to create two types of endpoints:
Consumer Endpoints
A Consumer endpoint's primary roll is to listen for messages on an external JMS destination and pass them into to the NMR for delivery to endpoints inside of the Red Hat JBoss Fuse container. Consumer endpoints can send responses if one is required.
Provider Endpoints
A Provider endpoint's primary roll is to take messages from the NMR and send them to an external JMS destination.
Note
The JMS binding component also supports non-Spring based endpoints. However, the non-Spring based endpoints are deprecated.
In most instances, you do not need to write any Java code to create endpoints. All of the configuration is done using Spring XML that is placed in an xbean.xml file. There are some instances where you will need to develop your own Java classes to supplement the basic functionality provided by the binding components default implementations. These cases are discussed at the end of this guide.

Key features

The Red Hat JBoss Fuse JMS binding component provides a number of enterprise quality features including:
  • Support for JMS 1.0.2 and JMS 1.1
  • JMS transactions
  • XA transactions
  • Support of all MEP patterns
  • SOAP support
  • MIME support
  • Customizable message marshaling

Contents of a JMS service unit

A service unit that configures the JMS binding component will contain two artifacts:
xbean.xml
The xbean.xml file contains the XML configuration for the endpoint defined by the service unit. The contents of this file are the focus of this guide.
Note
The service unit can define more than one endpoint.
meta-inf/jbi.xml
The jbi.xml file is the JBI descriptor for the service unit. Example 13.1, “JBI Descriptor for a JMS Service Unit” shows a JBI descriptor for a JMS service unit.

Example 13.1. JBI Descriptor for a JMS Service Unit

<jbi xmlns="http://java.sun.com/xml/ns/jbi" version="1.0">
  <services binding-component="false" 1
            xmlns:b="http://servicemix.apache.org/samples/bridge"> 2
    <provides service-name="b:jms" 3
              endpoint-name="endpoint"/> 4
    <consumes interface-name="b:MyConsumerInterface"/>  5
  </services>
</jbi>
The elements shown in Example 13.1, “JBI Descriptor for a JMS Service Unit” do the following:
1
The service element is the root element of all service unit descriptors. The value of the binding-component attribute is always false.
2
The service element contains namespace references for all of the namespaces defined in the xbean.xml file's bean element.
3
The provides element corresponds to a JMS provider endpoint. The service-name attribute derives its value from the service attribute in the JMS provider's configuration.
Note
This attribute can also appear on a consumes element.
4
The endpoint-name attribute derives its value from the endpoint attribute in the JMS provider's configuration.
Note
This attribute can also appear on a consumes element.
5
The consumes element corresponds to a JMS consumer endpoint. The interface-name attribute derives its value from the interfaceName attribute in the JMS consumer's configuration.
Note
This attribute can also appear on a provides element.

Using the Maven JBI tooling

The Red Hat JBoss Fuse Maven tooling provides two archetypes for seeding a project whose result is a service unit for the JMS binding component:
servicemix-jms-consumer-endpoint
The servicemix-jms-consumer-endpoint archetype creates a project that results in a service unit that configures a JMS consumer endpoint.
Tip
You can use the smx-arch command to in place of typing the entire Maven command. 
smx-arch su jms-consumer ["-DgroupId=my.group.id"] ["-DartifactId=my.artifact.id"]
servicemix-jms-provider-endpoint
The servicemix-jms-provider-endpoint archetype creates a project that results in a service unit that configures a JMS provider endpoint.
Tip
You can use the smx-arch command to in place of typing the entire Maven command. 
smx-arch su jms-provider ["-DgroupId=my.group.id"] ["-DartifactId=my.artifact.id"]
The resulting project will contain two generated artifacts:
  • a pom.xml file containing the metadata needed to generate and package the service unit
  • a src/main/resources/xbean.xml file containing the configuration for the endpoint
    Important
    The endpoint configuration generated by the archetype is for the deprecated JMS endpoints. While this configuration will work, it is not recommended for new projects and is not covered in this guide.
If you want to add custom marshalers, custom destination choosers, or other custom Java code, you must add a java folder to the generated src folder. You also need to modify the generated pom.xml file to compile the code and package it with the service unit.

OSGi Packaging

To package JMS endpoints as OSGi bundles you need to make two minor changes:
  • include an OSGi bundle manifest in the META-INF folder of the bundle
  • add the following to your service unit's configuration file: 
    <bean class="org.apache.servicemix.common.osgi.EndpointExporter" />
Important
When you deploy JMS endpoints in an OSGi bundle, the resulting endpoints are deployed as a JBI service unit.
For more information on using the OSGi packaging see Appendix H, Using the Maven OSGi Tooling.

Namespace

The elements used to configure JMS endpoints are defined in the http://servicemix.apache.org/jms/1.0 namespace. You will need to add a namespace declaration similar to the one in Example 13.2, “Namespace Declaration for Using JMS Endpoints” to your xbeans.xml file's beans element.

Example 13.2. Namespace Declaration for Using JMS Endpoints

<beans ...
      xmlns:jms="http://servicemix.apache.org/jms/1.0"
      ... >
  ...
</beans>
In addition, you need to add the schema location to the Spring beans element's xsi:schemaLocation as shown in Example 13.3, “Schema Location for Using JMS Endpoints”.

Example 13.3. Schema Location for Using JMS Endpoints

<beans ...
       xsi:schemaLocation="...
http://servicemix.apache.org/jms/1.0 http://servicemix.apache.org/jms/1.0/servicemix-jms.xsd
...">
  ...
</beans>