Java Web application developers now have new option with the newly published beta of the WebSphere Application Server Liberty profile. The nicest thing about this is that unit testing your Java applications is now just as quick and easy with WebSphere as it is with Tomcat. This new Liberty profile has the disk and memory footprint similar to Apache Tomcat. And it starts and stops in about the same time – between 1 and 5 seconds – depending on the number of applications deployed.This new Liberty profile has OSGi support, JPA, JDBC, Web applications (JSP, Servlets, JSF), and few other things not found in Tomcat.
The other good news is that you now have a choice between the full featured Rational Application Developer and vanilla Eclipse + IBM WAS plugin. Considering that the license cost for the developer setup of Eclipse + IBM WAS plugin + WAS for Developers is $Zero, and deployment into production version of WAS or WAS ND is transparent, this really leaves no reasons to use Tomcat on your development machine.