This is a java implementation of algorithm to find the centre of an arbitrary polygon. Where "centre" is defined as the centre of the largest circle that can be drawn within the polygon.
It is based on the process described in this paper http://arxiv.org/ftp/arxiv/papers/1212/1212.3193.pdf An Efficient Algorithm to Calculate the Center of the Biggest Inscribed Circle in an Irregular Polygon by OSCAR MARTINEZ. See https://github.com/omtinez/CenterPolygon for the version by the paper's author in C.
See also this newer approach: https://github.com/mapbox/polylabel