Wednesday, August 3, 2011

Reminder: hashcode is not a key

I just wanted to share a reminder not to treat Object.hashCode() as a key. This seems very basic, but I have seen experienced developers get tripped up over this method. A number of people seem to think that hashCode can be relied on to return unique integers for each object value, especially for strings. Oops.

My latest BlackBerry app: TempoBeat

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My latest BlackBerry app is out. Presenting: TempoBeat, an electronic metronome app. I paid quite a bit of attention to the user interface with this app, since I wanted something that works well with both a keyboard and a touchscreen. The controls can be manipulated by touch, but I also included a number of keyboard shortcuts for non-touch BlackBerry model. It has a bunch of features or characteristics typical of metronomes: tempo, beats per measure, volume control etc. This being a BlackBerry app, I added one more feature that truly belongs on a BlackBerry: you can use the iconic BlackBerry LED to blink the beats, in colors of your choice.