This is the Java OpenCV example straight from the official docs, but with pre-compiled libraries and usage instructions for OSX 10.9 (Mavericks). It may be useful for others who want to borrow my jar and dylib since they should only depend on OSX system libraries.

Compile:

javac -sourcepath . -cp classes:opencv-300.jar com/example/simple/simple.java -d classes

Run:

java -cp classes:opencv-300.jar com.example.simple.SimpleSample

I compiled OpenCV (172a5d42) starting from the official docs, but they are heavily geared toward Windows, so I had to improvise to get them to work on OSX 10.9 (Mavericks). The breakthrough for me was pulling up the CMake graphical configure to turn off all the libraries that were misbehaving (an iterative process) and to make it a static library build. It's possible that I could have used MacPorts, but my attempts early on were unsuccessful.