From java EE 7 tutorial
If no welcome file is specified, GlassFish Server will use a file named index.html as the default welcome file. If there is no welcome file and no file named index.html, GlassFish Server returns a directory listing.
It's right regarding to welcome file and index.html, but it doesn't work regarding to directory listing, is this wrong info from java tutorial or I didn't understand the quoted paragraph? if the problem on the tutorial, is there any comprehensive and reliable java ee tutorial?