Enterprise JavaBean (EJB) clients running on WebSphere Application Server 4.0 receive java.lang.NullPointerException when calling enterprise beans deployed in non-WebSphere Application Server
 Technote (FAQ)
 
Problem
This problem can occur if an EJB deployed in WebSphere® Application Server 4.0.x delegates requests to another EJB deployed in IONA's Orbix E2A Application Server. The transaction attribute is set to Mandatory in both beans. The WebSphere client is initiating transactions and sending requests to the WebSphere EJB, which delegates to IONA ASP bean.

This problem was reported to IONA and IONA said WebSphere is not sending "coordinator" within its Transaction Context, which is not satisfying the OTS v1.1 specification (in section "Structure of Propagation Context" of the OTS v1.1 specification).
 
Solution
WebSphere Application Server 4.0.x is an OTS 1.1-compliant transaction monitor. By default, however, the full interoperability mode for OTS 1.1 is turned off and WebSphere runs in native mode.

The information center section 3.6: Interoperability with WebSphere Application Server for z/OS describes turning on the interoperability mode within WebSphere Application Server. This information is equally applicable to any Java™ 2 Platform, Enterprise Edition (J2EE™) Application Server, not just to WebSphere Application Server for z/OS®.

Here is the relevant excerpt from information center, section 3.6: Interoperability with WebSphere Application Server for z/OS, about turning on the interoperability mode:

Interoperability between the Advanced Edition (AE) product and WebSphere Application Server for z/OS can be achieved by using RMI over IIOP to propagate transaction and security contexts.

Transactions
WebSphere provides this function by supporting distributed transactions involving enterprise beans running in both the AE and z/OS application servers. To enable the interoperability, set the following flags in an AE server’s JVM settings (system properties):

"-Dcom.ibm.ejs.jts.jts.ControlSet.nativeOnly=false"
"-Dcom.ibm.ejs.jts.jts.ControlSet.interoperabilityOnly=true"

To set the arguments with the administrative console:

  • Select the application server node in the administrative domain tree.
  • Click the JVM Settings tab.
  • Add the arguments to the System Properties list.


Important: Interim Fix PQ62277 should be applied to WebSphere Application Server versions 4.0.1, 4.0.2 & 4.0.3 when running in interoperability mode.
 
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server
Operating system(s): HP-UX
Software version: 4.0
Software edition:
Reference #: 1054605
IBM Group: Software Group
Modified date: Oct 27, 2004