TeaTimer

TeaTimer - a simple application to demonstrate accurate timing

This application shows how to implement a clock using deadlines. If you don't have an RTC or similar time counting device it is nearly impossible to design an application with accurate timing or equidistant time steps with a standard JAVA™ environment. You can do a sleep() for a second and then draw the clock again, then wait for another second, but while drawing there's time lost and you can't know how much it is. Even more JAVA™ is multi-threaded, so you can't know if another thread is stealing some more time of your seconds.

Using JControl deadlines you can specify that counting a second takes exacly one second, it is up to the virtual machine to guarantee this timing.

Usage

After startup you can set the brewing time using up/down (defaults to 3 mins), after pressing select the clock starts ticking. If the selected time span expires the buzzer beeps a couple of times, pressing a key aborts beeping and the program starts again but with the duration selected before. It is possible to break the count-down holding the "up" key.