Hibernate's core object/relational mapping functionality
Google maps for block game
Traccar GPS Tracking System
An open source geocoder for openstreetmap data
GeoServer repository
Mybatis common mapper, easy to use
Geographic library
Toolkit for working with and mapping geospatial data
Open source cross-platform Java Visual Traceroute
NMEA 0183 library for Java
GPS track editor for editing tracks and planning (multiple) day tours
Navigational Algorithms - Marine navigation
Set of Java interfaces for geospatial applications
Spatial Statistics Libraries & Tools for GeoTools, GeoServer, uDig
Open source system for GPS tracking devices