Investigating Hibernate Associations – Many to Many

In my previous posts, we have looked at one-to-one and one-to-many hibernate associations. This one is going to focus on many-to-many hibernate association.

Migrating from Tomcat 4.x to 5.5.x

A few days back my team needed to migrate an old production site. We were using Tomcat 4.1.x and the client wanted to use a more current Tomcat version in order to gain advantage of newer optimizations. Our operating environment is Linux.

The migration happened to be a piece of cake. We needed to do just two things.

• Made the following changes in my Tomcat startup script:

The earlier startup script was as below:

export CATALINA_BASE=/opt/jakarta-tomcat-4.1.31/instances/application
cd /opt/jakarta-tomcat-4.1.31/bin
sh startup.sh
cd $HOME

The CATALINA_BASE pointed to my web application home, the next line used the earlier version of tomcat. Just change /opt/jakarta-tomcat-4.1.31/bin to opt/apache-tomcat-5.5.23/bin and you will be using the newer tomcat server version.

• Replaced the 4.1 server.xml file with 5.5 server.xml:

I tried retaining the 4.1 server.xml but it started giving weird errors. I took the 5.5 server.xml made the necessary customizations to it and deployed and started the server.

On the whole the migration has been pretty smooth. Even better than my expectations.