Fix build issues with Open JDK 13, see discussion in #1730.
Fix build issues with Open JDK 13, see discussion in #1730.

graphhopper/graphhopper,boldtrn/graphhopper,boldtrn/graphhopper,ammagamma/graphhopper,ammagamma/graphhopper,graphhopper/graphhopper,fbonzon/graphhopper,fbonzon/graphhopper,ammagamma/graphhopper,routexl/graphhopper,don-philipe/graphhopper,boldtrn/graphhopper,devemux86/graphhopper,don-philipe/graphhopper,routexl/graphhopper,boldtrn/graphhopper,fbonzon/graphhopper,graphhopper/graphhopper,devemux86/graphhopper,routexl/graphhopper,devemux86/graphhopper,don-philipe/graphhopper,fbonzon/graphhopper,graphhopper/graphhopper,don-philipe/graphhopper,ammagamma/graphhopper,routexl/graphhopper,devemux86/graphhopper