Special considerations with chaining Web Services

If you use chained Integration Objects within a ZIETrans Web service, you are creating a stateful Web service. ZIETrans runtime does not store data between invocations of chained Integration Objects in the same Web service. However, ZIETrans runtime does require that the next in chain Web service invocation is routed back to the same instance of the ZIETrans runtime so that the next in chain IO will use the same Telnet connection.

If you deploy a stateful ZIETrans Web service using JAX-RPC support to a cluster, to enable all Integration Objects in the chain to use the same Telnet connection, do one of the following:
  • Create the ZIETrans Web services from EJB Access Beans. The ZIETrans EJB is a stateful session EJB, so the EJB client always interacts with the same ZIETrans EJB instance.
  • Configure the scope of the Web service to be session (this can be done in the development environment or after deployment), and use SESSION_MAINTAIN_PROPERTY in the Web service client runtime to maintain the session across invocations, therefore ensuring HTTP session affinity. For more information about stateful Web services, see the following article: http://www-128.ibm.com/developerworks/webservices/library/ws-tip-stateful.html. Note that WebSphere® APAR PK35259 may be required, as it fixes an issue with SESSION_MAINTAIN_PROPERTY.
If you deploy a stateful ZIETrans Web service using JAX-WS support to a cluster, to enable all Integration Objects in the chain to use the same Telnet connection, do one of the following: