GraphHopper
GraphHopper is a fast and Open Source road routing engine.
Is fast and memory efficient
Works with OpenStreetMap data
Business-friendly due to Apache License
Scales from big server to mobile device
Implemented in Java™
Works on Android and Raspberry Pi
Has a large test suite
Highly customizable
1 OpenStreetMap 地图数据 （china-latest.osm.pbf和china-latest-free.shp）
China：https://download.geofabrik.de/asia/china.html
2 git graphhopper
https://github.com/graphhopper/graphhopper
数据基元
https://wiki.openstreetmap.org/wiki/Elements
Nodes: 点----空间位置
Ways:路---线或区域 2到2000个点组成
Relations：关系----上述对象之间的关系（路径relation 转向relation 多边形）
Tag：属性数据----矢量基元