I am trying to calculate a route based on either geographic location or address. I figured the obvious way would be to use some part of the built-in Google Maps package, but it proved harder than assumed. There used to be a package called com.google.googlenav, but from that disappeared with the 1.0 release of the Android SDK.
I know that Google Maps has a public JavaScript API, but since the application is developed for the Android (in Java) and I would like to have an offline alternative, is there any other library packages, built-in or 3rd party, that I can use to achieve this?
If I understand it correctly you need Java-library that find routes (not the off-line solution).
You may try Java API for CloudMade services:
http://developers.cloudmade.com/projects/show/java-lib
CloudMade makes services around OpenStreetMap data, so it may be different from output of Google Maps. However OpenStreetMap is growing, and now could already compete with GMaps in many European countries.