I am doing a website about places to visit using java, gwt, gae, gwt-platform and objectify for the datastore and GWT maps V3 [github.com/twistedpair/GWT-Maps-V3-Api]. (I don’t know if is the best solution but for now im advancing, slowly but ok :))
Question:
What you think can be the best approach to store latitude and longitude of a place being able later to search places near it?
I was trying the approach to save the longitude and latitude into strings using lexicographical order using
http://code.google.com/p/sappenin/source/browse/trunk/SappeninUtils/src/main/java/com/sappenin/util/BigDecimalStringCodec.java?r=146
But I didn’t achieve to get it working and as I understand, I would have to query first by latitude and then by longitude and I think it wont be practical at all.
I don’t know if is better to use GeoPt in my entities or only the values latitude and longitude as two strings or long (as bigdecimal is not supported). I think will be more or less the same because internally GeoPt is the same, two numbers.
I think the best approach will be geomodel but is in python then I started to check http://code.google.com/p/javageomodel/
But I couldn’t manage, the problem is that geomodel is not for objectify. I found an approach of javageomodel for objectify but seems quite old.
[github.com/bfuster/javageomodel]
I would try to take the original javageomodel and try to modify it but I wanted to know if someone knows a better way to do this.
Which option you recommend? Maybe there is a very easy way to do it now in 2012 but I couldn’t find it and I’m rounding around one week through Google.
Thank you in advance for your opinion!
I hope the question is more or less clear because as you can see, I have a huge mess in my mind right now, 😉
You can find an example of how to use geohashing with GAE and Objectify here:
https://github.com/stickfigure/motomapia
The demo is here:
http://www.motomapia.com/
The geohash library is here:
http://code.google.com/p/javageomodel/