Java APIs

This part of sockets is just needlessly confusing. Perhaps someone can shed some light on this?

Sometimes I get an IOException with as message "Connection reset by peer". Other times, it's "broken pipe". What is the difference? Why isn't there a way other than parsing the exception message text to figure out if it's a client 'hanging up on you' unexpectedly or something else?

Secondly, in my NIO server, all webbrowsers, but for some reason firefox especially, really likes to make a full request, than grab 0 to 99 bytes (the full return HTTP message size is much larger than that), and then silently hang up and immediately re-request the same resource again. Sometimes 10 to 15 times in a row. Firefox shows no errors of any kind when it does this. the read() operation on the socket returns -1 which is what ends up causing the close.

Is this because '-1' doesn't really mean: The socket is closed, it actually just means: the socket INPUT is closed but you can still send?

And if it is the latter, how the heck do I detect a connection in lockdown state in a non-blocking environment?