Pro Flex on Spring is the first book covering the use of the Spring Framework as an integration point for the Flex Framework so that enterprise Java developers can now add a Rich Internet Application front end to their “back-end”. Flex on Spring completes the Spring Framework, and makes it arguably the most complete, top-down, application development stack available to Java developers.

What you’ll learn:
• Explore best practices on architecting enterprise Rich Internet Applications
with Flex and Spring.
• Discover how Flex applications interface with Spring services.
• Understand how to persist data, end–to–end, using Flex data communication protocols
with Spring and its interactions with iBATIS, Hibernate, and JDBC.
• Work with solid frameworks, Cairngorm and Pure MVC, to build Flex applications.
• Build a practical application that demonstrates real experience in delivering enterprise RIAs.
• See how Spring Factories play a key role in routing calls to Spring classes from Flex clients.

The first Java Option parameters to set are -Xms (minimum heap size) and -Xmx (maximum heap size). I usually start with a lower -Xms number so the heap can build up to the max -Xmx size if needed. This way I do not partition a portion of memory that may not be used. The setting I use on development and production servers is:

 -Xms 256m -Xmx 1024m

The second Java Option to look at is the MaxPermSize. The permanent generation is used to hold reflective data of the VM itself such as class objects and method objects. PermSize is an addition to the -Xmx value. I have set the following MaxPermSize in development and production:

-XX:MaxPermSize=128m

You can set these parameters in Tomcat using the Configure Tomcat application on the Java VM tab.

Be sure you have enough memory on the web server you are allocating memory for. The Windows servers I am referring to have 4 gigs of RAM.