For those who have an existing JBoss 4/5/6 installation, migrating to JBoss 7 will take slightly more time, as the new archicture of JBoss has a completely new directory layout and configuration mechanism.
For starters, you should set up your datasources. This is described in the following article:
http://community.jboss.org/wiki/DataSourceConfigurationInAS7
when you’ve done that and setup your MySQL or Oracle datasource bindings and modules, you’ll have to configure your application for usage in a JBoss 7 / JEE 6 Environment.
First of all, you’ll have to check your persistence.xml and your references to see if they comply with the new JEE 6 specs. This is explained in depth in the following section of the JBoss 7 guides:
https://docs.jboss.org/author/display/AS7/Developer+Guide#DeveloperGuide-JNDIPortableJNDISyntax
Next, you will have to check your application for external dependencies, i.e. all libs that were formerly deployed to the /server/<instance>/lib directory need to be installed as modules and declared as dependencies in the
MANIFEST.MF file
Depending on which components your application uses, you may need to add one or more dependencies to this file. There is more information about these dependencies in the following paragraphs.
NOTE: If you modify this file, make sure to include a newline character at the end of the file.
If you need to port your Resteasy application parts, please observe this excellent and short tutorial:
http://blog.xebia.com/2011/07/developing-restful-applications-on-jboss-as-7/
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