An objectoriented API for KML (the Google Earth format), was opensourced.
From the project description: "...The main goal of the Java API for KML (JAK) is to provide automatically generated full reference implementation of the KML object model defined by OGC’s KML standard and Google’s GX extensions. It is an object orientated API that enables the convenient and easy use of KML in existing Java environments.
KML is an XML-based language schema that describes and visualizes geographic data. The language is often used in 2D web based maps and 3D virtual globes. Originally developed for Google Earth as a means of maintaining and exchanging geographical data, the language was defined by the Open Geospatial Consortium (OGC) as a standard in April 2008. So far, many virtual globes, like for example NASA’s Earth Wind and Microsoft’s Virtual Earth, have adopted the KML language as their data format of choice..."