GData, Google data API, provides a simple standard protocol for reading and writing data on the web, which supports two common XML-based syndication formats (Atom and RSS).

Briefly browse the documents and javadoc of GData, I found that it is very similiar to my thought on my current clustering searching engine system, designing an interface of data structure for all the request to searching engine servers, and employing an other interface to handle external/internal requests and fill up the data structure.

Although my first version of searching engine has been deployed on LiveDigital, I am still working on the new version with clustering design. source code has been packaged and implementation document is almost done, I still hope I can learn something from GData, more professional and structrual design.