In This Section
Overview
The JMS binding works with JMS 1.1 level JMS clients and is configured using JNDI lookup. In addition to JNDI lookup the platform provides a subclassed version of the JMS binding optimized for working with ActiveMQ.
Bus Descriptor Format
A jms message bus can be configured via a descriptor string as follows which takes the connection information followed by a list of provider properties.
jms://<address>:<port>&prop1=val1&propN=valN
An example bus descriptor for using tibco ems
jms://tibcohost:2732&username=admin&password=changeme / &jndi=true / &jndi_contextfactory=com.tibco.tibjms.naming.TibjmsInitialContextFactory / &jndi_principal=admin / &jndi_credentials=changme / &jndi_connectionfactory=CSTopicConnectionFactory
DDL
In a DDL config file a jms bus can equivalently be configured in one two ways
Decomposed
As A Descriptor
Note the '/' denoting line breaks above would not be valid in actual XML – they are provided here for readability.
The descriptor form is useful in cases where the descriptor name may be supplied as an external configuration property that is substituted for example:
Default to loopback for testing
Generic JMS Binding Properties
The following properties can be set in the descriptor used to create a JMS bus binding.
| Property | Default | Description |
|---|---|---|
jndi | true | Indicates that JNDI should be used to lookup the connection factory for creating JMS connections. |
jndi_contextfactory | - | The name of the environment property for specifying the initial context factory to use |
jndi_principal | - | The name of the environment property for specifying the identity of the principal for authenticating the caller to the service |
jndi_credentials | - | The environment property for specifying the credentials of the principal for authenticating the caller to the service |
jndi_connectionfactory | - | The name of the connection factory to look up in jndi. |
When using jndi the address portion of the binding descriptor is used as the address at which to lookup the connection factory. The returned connection factory may connect to a different host.
The ActiveMQ Binding
While ActiveMQ can be configured via JNDI like any other JMS provider, the platform provides a custom 'activemq' bus provider.
The ActiveMQ binding is additionally optimized to:
- Use ActiveMQ's INDIVIDUAL_ACKNOWLEDGE_MODE for channels using Guaranteed delivery.
- Normalize subscribe and send calls to replace '/' delimited topics with '.' delimited topics which allows the same channel key configuration as other platform bindings.
DDL
In a DDL config file a activemq bus can equivalently be configured in one two ways
Decomposed
As A Descriptor
Sending and Receiving from External Applications
This section describes how to send to Talon applications from non Talon applications and from Talon application to non Talon applications over jms. The sections below utilize ADM generated messages for convenience, but this is not required. For example, if you your messages are encoded in protobuf (or Xbuf) you could encode/decode the message yourself without using ADM. One such example of this might be if you were using C and generated protobuf message from the IDL generated by ADM.
Sending Messages To Talon
The platform's JMS binding encodes a serialized message payload in a bytes message and sets metadata fields in its jms headers. The following example show
Receiving Messages from Talon
The following code sample shows how an external application using the JMS api directly can unpack a message sent over the platform's built in JMS binding and materialize it into a message view.