The OpenLR encoder and decoder use interfaces for their input and output data. The following sketches outline the workflow and the usage of the interfaces provided by the OpenLR data package.
The encoding process starts with the creation of a (map-dependent) location. The LocationFactory in the OpenLR encoder package provides several methods for creating point and line locations.
The OpenLR encoder takes such a location as input for the encoding process. It generates a raw location reference which is the input for all physical encoders. These physical encoder generate the different location reference formats. These formats implement the location reference interface.
The decoding process needs a (map-independent) location reference as input. There can be several different implementations of this interface as there are different physical formats available.
The physical decoder takes this location reference and translates the data into a raw location reference. This step also depends on the physical format being used. Such a raw location reference is used by the OpenLR decoder to find back the location.
The legend below shows the interpretation of the symbols. Interfaces are shown as a circle, components are drawn as a rectangle, implementations of an interface are drawn as a dashed rectangle, and factories are drawn as dashed rectangles with rounded edges.
The implementations of an interface within the different physical formats may have different names and therefore "{PF}" stands for the name of the physical format.
