Java port of Dominic Mazzoni's libresample 0.1.3, which is in turn based on Julius Smith's Resample 1.7 library.
There's no documentation for the Java port, but for the most part it's just like the C version which you can read about here: https://ccrma.stanford.edu/~jos/resample/Free_Resampling_Software.html
Also take a look at the C version's README which is bundled in the libresample-0.1.3.tgz archive.