I'll interpret that to mean that you want to be able to read from
System.in without waiting for the user to press enter - is that right?
If so, it's your OS console, not Java's buffering of System.in that
prevents it, and consequently unbuffering System.in (alone) won't let
you do it.
On unix-like platforms, you can use "stty -icanon min 1" to change
console mode so you can do character-at-a-time input. On other
operating systems, I have no idea.
I tried a few different combinations of input streams, only after using 'stty -icanon min 1' can I read input without waiting for an 'Enter'. This is on linux.
Is this kind of 'unbuffered' input from console enabled by default on windows? I remember writing C programs to read standard input without waiting for an 'Enter' on windows systems.