I store my geographical information in PostgreSQL database.

I want to use GraphHopper for my routing propose, but GraphHopper can read information in shapefiles or OSM format. I now convert my information to shapefile format and use GraphHopper. But I want to read information directly from PostgreSQL and for this propose I have to write a custom reader for this.

How can write this reader?

closed as too broad by Vince, mgri, Andre Silva, whyzar, Mapperz May 8 '17 at 14:14

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Welcome to GIS SE. As a new user please take the Tour, which explains how our "Focused question / Best answer" database works. Coding questions require code, but this "How can I write a custom reader" is so broad, I'm voting to close it as just too broad, since this is not a tutorial site. – Vince May 8 '17 at 11:22