Although you don't need any additional libraries to typical activity, eg. there is no need to import RIDC API for WebCenter 11g UCM related ADF task flows, but still you will need additional tools to interact with UCM objects from your code.
The RIDC API is a lightweight "wrapper" around WS UCM interface. With this library we can acces UCM objects in plain java style, cause RIDC is a plain java object. You don't need work with webservices bloat no more.
To add RIDC as a JDevelor external add-on, you should run JDeveloper and next run menu Help | Check for updates.
In source tab select Install From Local File and browse filesystem to find oracle.ucm.ridc.jdev-11.1.1.zip. Usually you can find the file in: $Middleware_home\$Oracle_ECM_home\ucm\Distribution\RIDC\jdev\.
Above file contains all prerequisites sufficient to install RIDC in JDeveloper environment. Simply select Next button and run installation process.
