graphhopper | Open source routing library and server using OpenStreetMap

graphhopper is a Java library. graphhopper has no bugs, it has no vulnerabilities and it has low support. However graphhopper build file is not available and it has a Non-SPDX License. You can download it from GitLab.

GraphHopper supports several routing algorithms, such as Dijkstra and A* and its bidirectional variants. Furthermore, it allows you to use Contraction Hierarchies (CH) very easily. We call this speed mode; without this CH preparation, we call it flexible mode. The speed mode comes with very fast and lightweight (less RAM) responses, although it does not use heuristics in its default settings. The downsides are that the speed mode allows only pre-defined vehicle profiles (multiple possible in GraphHopper) and requires a time consuming and resource-intensive preparation. Then there is the hybrid mode which also requires preparation time and memory, but it is much more flexible regarding changing properties per request or e.g. integrating traffic data and more. Furthermore, this hybrid mode is slower than the speed mode, but it is an order of magnitude faster than the flexible mode and uses also less RAM for one request. You can switch between all modes at request time.