I coded a modest Java implementation of the Perona & Malik anisotropic diffusion, based on the ImgLib2 library. You can find it here.
You will have to import and learn how to use the ImgLib2 library though. Here is an example using the anisotropic diffusion algorithm.
Otherwise, here is a 2D only implementation, by Vladimir Pilny and Jiri Janacek, made for the ImageJ software.
And here is another one for ImageJ as well, by Christopher Mei.
Best regards.