It is really helpful when debugging AJAX application to see the traffic between the the web browser and the client. You can do this using the HTTP Analyzer; but it can get really annoying to have to set and reset your proxy settings in the browser.
It turns out that if you are using firefox you can get around this by using named profiles. The following assumes Linux, but windows people can just clag on .exe to the commands. One thing you have to understand is that by default the firefox command will just open a window on your currently open instance of firefox so you need to use "-no-remote" to create a separately configured instance. So from the command line run:
firefox -no-remote -CreateProfile Debugging
Now just quickly start a firefox with this profile so you can configure the proxy settings to use the analyzer in JDeveloper. (localhost, 8099 and no host exclusions)
firefox -no-remote -P Debugging
So you need to configure JDeveloper to start this special firefox every time, simply go to Tools->Preferences and paste in this command line. It is likely that JDeveloper will complain it cannot verify it and underline it in red; but it does seem to work okay:
So all you have to do is to start the HTTP Analyzer and run HTML/JSP/JSF page from within JDeveloper and a new instance of firefox using the Debugger profile will be started. The downside is that this is less memory efficient as for each run you will be creating a new copy of firefox; but it seems worth it to simplify development.
Annoyingly this trick can't use used directly to configure the java script debugger, due to a bug in the handling of command lines. A work around might be to create a wrapper script for firefox that passed on the above parameters along with any passed values. Don't have time to try that today though.