Oracle User Messaging Service Component Characteristics

5-56 Oracle Fusion Middleware High Availability Guide Figure 5–28 Oracle User Messaging Service Single-Instance Architecture

5.9.1.1 Oracle User Messaging Service Component Characteristics

This section describes the characteristics of Oracle UMS components. UMS Server is made up of the following: ■ Message driven beans MDBs that dequeue messages from JMS queues ■ Stateless session beans to implement messaging business logic ■ JAX-WS servlets to implement the messaging web services ■ A simple Oracle ADF Faces user interface component for managing end user messaging preferences. UMS drivers typically contain the following: ■ JCA resource adapter embedded within the EAR in order to interface with external protocol gateways Configuring High Availability for Oracle Fusion Middleware SOA Suite 5-57 ■ Two MDBs, one for inbound, and one for outbound, that interface between the resource adapter and the JMS queues ■ Some UMS drivers that implement an HTTP-based protocol, such as VoiceXML, have a servlet module as well. UMS client applications that use the EJB interface have a stateless session bean that provides the API used by client business logic, and an MDB to asynchronously receive inbound messages. UMS depends heavily on JMS. JMS queues are also used to buffer content between clients and servers, and between servers and drivers. Each typical messaging operation sending an outbound message or receiving an inbound message involves two JMS queues, one between the client and server, and one between the server and driver. UMS messaging state is stored in the database and in persistent JMS queues. External Dependencies UMS depends on an external database repository to maintain message and configuration state. It shares this state between clustered instances. The UMS Server accesses the database using a Java EE JDBC data source provisioned at installation time. This data source is a non-XA data source. Therefore, UMS does not depend on the JTA capabilities of the underlying infrastructure. UMS uses JMS to deliver messages among messaging applications. By default it is configured to use a file-based persistent JMS store, therefore it depends on the storage device where those files are located.

5.9.1.2 Oracle User Messaging Service Startup and Shutdown Lifecycle