"java.io.IOException: Mismatched serialization UIDs" errors

Technote (FAQ)
Problem
What causes "java.io.IOException: Mismatched serialization UIDs" errors
Solution
"java.io.IOException: Mismatched serialization UIDs" errors can be difficult to resolve. They are caused by a discrepancy between a java RMI or EJB client and server in how they calculate object identifiers for objects they are sending to each other.

Some known causes and workarounds:

  • Splitting an EJB application and server between the VisualAge for Java WebSphere Test Environment WebSphere. Calling remote methods that send or receive complex objects from within the VisualAge IDE to WebSphere, or running a java client from a command line which accesses the WebSphere Test Environment within Visual Age, can cause this problem. A workaround is to run both the client and server components of an application within VisualAge, or outside of VisualAge. In the case of a developer writing and testing a new client that accesses an existing EJB, this will may mean importing and deploying the EJB into VisualAge.
  • Communicating between different versions of WebSphere. This error has cropped up with developers who use a WebSphere 3.02 admin console, monitoring a WebSphere 3.02.1 server. The error appeared in the window from which the console had been started, when they tried to start the ResourceAnalyzer. The console then crashed. Upgrading the admin console to 3.021 resolved the problem.
  • Using classes from other ORB products in WebSphere. The error occured when developers placed ComponentBroker classes on WebSphere's classpath property in the admin.config file. The developers experienced the error when testing their own EJB-based application. The errors disappeared when the developers placed the eablib.jar file ahead of the ComponentBroker .jar files in WebSphere's classpath.
Historical Number
02052,122











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, Servlet Engine/Web Container
Operating system(s): All Platforms
Software version: 3.0.2, 3.0.2, 3.5
Software edition: Standard, Advanced
Reference #: 1000951
IBM Group: Software Group
Modified date: 2000-09-01