Making Maps Navigable - Programming GPS and OpenStreetMap Applications with Java - page 114

Figure8.2. A digital map with political borders and routes between Hamburg,
Berlin, and Hannover.

Note that the link compiler has been kept as simple as possible, but it is
worth mentioning that for a more sophisticated compiler links should not
only be split. They should also be joined if exactly two links share one end
node.

8.4 Creating a NavigableMap

By now it should be clear that the map compilation process is very volatile
as it uses various (interdependent) tools with different paradigms. While
the link compiler relies on the integrity of an OSM file and is pretty numb
to map data, the NavigableMap 4 will be based on the org.w3c.dom.Document
with implied xml validations. The link compiler is part of the map compi-
lation (preparation) step, while the navigable map will be a vital software
component for navigation to proceed in the prototype development accord-
ing to the vision (see Figure 8.2).
This section will focus on the internal development of the navigable
map with the goal to create a graph to represent the navigable network in a
software environment. The methods actually applying the graph externally
for navigation will be added in Section 9.4
Note that the NavigableMap.java file is split into a top part for external
methods for navigation and a bottom for the construction phase with the
main method in the middle.

4 Collections and xml structures are described in terms similar to digital map data.
Do not get confused by name clashing, i.e., java.util.NavigableMap<K,V> !