Download of jtransforms-2.4-doc.zip (jtransforms-2.4-doc.zip ( external link: SF.net): 275,939 bytes) will begin shortly. If not so, click link on the left.
JTransforms is the first, open source, multithreaded FFT library written in pure Java. Benchmark results show better performance than FFTW. The latest version is available at http://github.com/wendykierp/JTransforms.