user manual

2 Upgrading WebLogic Server 4.5 and 5.1 to Version 7.0
2-30 BEA WebLogic Server 7.0 Upgrade Guide
Null Attributes
Due to a change in the JSP specification, null request attributes now return the string
"null" instead of an empty string. WebLogic Server versions since 6.1 contain a new
flag in
weblogic.xml called printNulls which is true by default, meaning that
returning "null" is the default. Setting
printNulls to false ensures that expressions
with "null" results are printed as an empty string, not the string "null."
An example of configuring the
printNulls element in weblogic.xml:
<weblogic-web-app>
<jsp-param>
<param-name>printNulls</param-name>
<param-value>false</param-value>
</jsp-param>
</weblogic-web-app>
JVM
WebLogic Server 7.0 installs the Java Virtual Machine (JVM), JDK 1.3.1_02, with the
server installation. The
setenv.sh scripts provided with the server all point to the
JVM. The latest information regarding certified JVMs is available at the Certifications
Page.
RMI
The following tips are for users porting to WebLogic Server 7.0 who used RMI in their
previous version of WebLogic Server:
 Re-run the WebLogic RMI compiler, weblogic.rmic, on any existing code to
regenerate the wrapper classes so they are compatible with WebLogic Server 7.0.
 Use java.rmi.Remote to tag interfaces as remote. Do not use
weblogic.rmi.Remote.
 Use java.rmi.*Exception (e.g., import java.rmiRemoteException;). Do
not use
weblogic.rmi.*Exception.