Use osmosis as a library in a java application

General talk
1

Hello.

I am trying to use osmosis into a java application (so as a lib). Unfortunately, there is no documentation whatsoever on how to do so and it is not trivial as osmosis seems to call a lot of different class layers to perform such an easy task as reading a pbf file… (it’s all abstracted behind plugin tasks so it is clearly not easy to go in for a newbee like me).
So is anyone on this forum, familiar with osmosis source code, that could help me by telling me how I can:

  • read an xml or pbf file
  • extract the information I want based on some tag values (for exemple, If I want to extract all ways of the type “highway” and their associated nodes, do osmosis keep a record of the nodes already parsed somewhere or do I have to read the osm file once again to extract the data for nodes associated to my highways? In the command line parametters, there is the “–used-nodes” option to do this but I couldn’t determine if in that case osmosis would read the osm file once again or if it had all the nodes already parsed recorded somewhere (in memory or in a temporary indexed file on disk)

Thanks

2

I’ve not used it, but https://wiki.openstreetmap.org/wiki/Osmium at least advertises and documents its use as a library.

3

Osmosis (java) and Osmium (C++) are two complete different things…

4

Indeed, but they do both do (or are advertised to do) some of the same things.

5

For parsing the xml or pbf file, check my old answer on help and the forum post linked there:

https://help.openstreetmap.org/questions/20695/lib-for-java-obf-pbf-or-other-format

You can chain this together with other functionality (Osmosis is essentially a pipeline of sequential processing steps). One of those should be tag-based filtering, although I haven’t done that yet myself. I’m going to have a look at the code, maybe I can figure it out.