By default, remote debugging is not enabled. You can enable it - default port is 8787.
In the file standalone.conf.bat
in the <JBOSS_HOME>/bin
folder, just uncommnet the following line:
rem Sample JPDA settings for remote socket debugging
set "JAVA_OPTS=%JAVA_OPTS% -agentlib:jdwp=transport=dt_socket,address=8787,server=y,suspend=n"
Then restart JBoss.
Remote Debugging will then be enabled.
You can then create a run time configuration in Eclispe to run and debug your apps in the JBoss app server.