Version mkgmap-r3314 was committed by steve on Sat, 12 Jul 2014 Rename two argument remove() methods in MultiHashMap and MultiIdentityHashMap for java 8. In java 8 there is a method of the same name but different signature on Map. So these classes don't compile on java 8. Renamed as removeMapping(), which is the same name used by apache collections which faced a similar problem. Note that the resulting map tiles are different when using java 7 and java 8. At least some of this appears to be due to different iteration order in maps, but there may be more serious problems - I don't know.