railroutes_web2 | Demonstrates using a graph database

railroutes_web2 is a Java library. railroutes_web2 has no bugs, it has no vulnerabilities and it has low support. However railroutes_web2 build file is not available. You can download it from GitHub.

This demo Java command-level web application refers to an embedded Neo4j graph database containing publicly available railroad locations. A graph database consists of nodes connected by links. Nodes and links can have name / value properties. The DBMS provides an API to navigate the resulting graph. A Lucene index enables an application to find a node-of-interest. In our case, each node is a integer-numbered "station" from a subset of public 1996 census data of the USA railroad network. A link (track) connects two stations. Each link has a node-to-node distance property. Neo4j has a built-in A* shortest path algorithm that returns an iterator across the shortest path through the graph of "stations". Our mobile / desktop web application uses a "from" and "to" slider to select rail station route endpoint numbers (1..133752) to compute a shortest path route between the two stations. A server-side controller calls Neo4j to obtain an iterator used to emit Google KML for the shortest path between the two stations. The controller is independently addressable via a URL. A browser-side button click handler reads the station slider values. Then it uses a Google API to insert a KML layer into a Google Map of the USA. The insertion API takes our controller URL as a parameter, thus obtaining the KML for the route layer.