Forward Ports on Parallels
Solution 1:
Can you access your testing server on :8080 from other real machines on your network? It could be that your development server software accepts only connections from your local machine (127.0.0.1 aka localhost).
Solution 2:
Jake's answer worked for me, too. On jboss, just start the server with
-b 0.0.0.0
and access it via
http://COMPUTERNAME:8080
Note: no need to use "local"
Related: Access localhost on Mac OS X from Parallels machine