 |  |  |  |  |
| | | | |
 |  |
In FUSE Services Framework, WS-RM functionality is implemented as interceptors. The FUSE Services Framework runtime uses interceptors to intercept and work with the raw messages that are being sent and received. When a transport receives a message, it creates a message object and sends that message through an interceptor chain. If the application's interceptor chain includes the WS-RM interceptors, the application can participate in reliable messaging sessions. The WS-RM interceptors handle the collection and aggregation of the message chunks. They also handle all of the acknowledgement and retransmission logic.
The FUSE Services Framework WS-RM implementation consists of four interceptors, which are described in Table 9.1.
Table 9.1. FUSE Services Framework WS-ReliableMessaging Interceptors
| Interceptor | Description |
|---|---|
org.apache.cxf.ws.rm.RMOutInterceptor |
Deals with the logical aspects of providing reliability guarantees for outgoing messages. Responsible for sending the Also responsible for aggregating the sequence properties—ID and message number—for an application message. |
org.apache.cxf.ws.rm.RMInInterceptor | Responsible for intercepting and processing RM protocol messages and SequenceAcknowledgement
messages that are piggybacked on application messages. |
org.apache.cxf.ws.rm.soap.RMSoapInterceptor | Responsible for encoding and decoding the reliability properties as SOAP headers. |
org.apache.cxf.ws.rm.RetransmissionInterceptor | Responsible for creating copies of application messages for future resending. |
The presence of the WS-RM interceptors on the interceptor chains ensures that WS-RM protocol messages are exchanged
when necessary. For example, when intercepting the first application message on the outbound interceptor chain, the
RMOutInterceptor sends a CreateSequence request and waits to process the original
application message until it receives the CreateSequenceResponse response. In addition, the WS-RM interceptors add
the sequence headers to the application messages and, on the destination side, extract them from the messages. It is not necessary to
make any changes to your application code to make the exchange of messages reliable.
For more information on how to enable WS-RM, see Enabling WS-RM.
You control sequence demarcation and other aspects of the reliable exchange through configuration. For example, by
default FUSE Services Framework attempts to maximize the lifetime of a sequence, thus reducing the overhead incurred by the out-of-band
WS-RM protocol messages. To enforce the use of a separate sequence per application message configure the WS-RM source’s
sequence termination policy (setting the maximum sequence length to 1).
For more information on configuring WS-RM behavior, see Configuring WS-RM.
| |  | |
 |
