gnu.io.PortInUseException: Unknown Application

Hello all,

I am using the Arduino Uno working on a mac. The basics seem to work so far: I can write and execute Sketches.

I tried using a java program to read the information from the serial port, using what I found on arduino.cc/playground/Interfacing/Java. However, I can't seem to get the port name right. While enumerating the ports I get 6 options, and none of them seem to work. The Arduino tool seems to use the first option, called "/dev/tty.usbmodem1d11". However, I get a gnu.io.PortInUseException: Unknown Application, whenever I try to use it.

Any hints on where to proceed?

Thanks!

Make sure the port isn't already in use (perhaps by the Arduino application itself).