Chapter 3. Getting started with Seam, using seam-gen
Seam includes a command line utility that makes it easy to set up an Eclipse project, generate some simple Seam skeleton code, and reverse-engineer an application from a preexisting database. This is an easy way to familiarize yourself with Seam.
In this release, seam-gen works best in conjunction with JBoss Enterprise Application Platform.
seam-gen can be used without Eclipse, but this tutorial focuses on using seam-gen with Eclipse for debugging and integration testing. If you would prefer not to use Eclipse, you can still follow this tutorial — all steps can be performed from the command line.
3.1. Before you start
Make sure you have JDK 5 or JDK 6 (see Section 37.1, “Java Development Kit Dependencies” for details), JBoss Enterprise Application Platform 5 and Ant 1.7.0, along with recent versions of Eclipse, the JBoss IDE plugin for Eclipse and the TestNG plugin for Eclipse correctly installed before you begin this tutorial. Add your JBoss installation to the JBoss Server View in Eclipse. Then, start JBoss in debug mode. Finally, start a command prompt in the directory where you unzipped the Seam distribution.
JBoss has sophisticated support for hot redeployment of
WARs and EARs. Unfortunately, due to bugs in JVM, repeat redeployment of an EAR (common during development) uses all of the JVM's perm gen space. Therefore, we recommend running JBoss in a JVM with a large perm gen space during development. If you are running JBoss from JBoss IDE, you can configure this in the server launch configuration, under "VM arguments". We suggest the following values:
-Xms512m -Xmx1024m -XX:PermSize=256m -XX:MaxPermSize=512m
The minimum recommended values are:
-Xms256m -Xmx512m -XX:PermSize=128m -XX:MaxPermSize=256m
If you are running JBoss from the command line, you can configure the JVM options in
bin/run.conf.
