Unit of Geotools' getArea function

I have Polygons with WGS84/EPSG:4326 coordinates (like 13.57933804767844,52.5126298984133) and use the Polygon.getArea function to obtain the area of the polygon. But the result I get is something like 7.695432394893684E-8 . There were similiar questions (see here, here or here) but although some of them are marked as answered, there is not an answer which helped me. I would like to convert the result to squaremeter. How can I do this?