The DSI utilities are a mish mash of classes accumulated during the last ten years in projects developed at the DSI (Dipartimento di Scienze dell'Informazione, e.g., Information Sciences Department) of the Università degli Studi di Milano. You can have a look at the Javadoc overview to have an idea of what's in.
The DSI utilities are distributed under the GNU Lesser General Public License.
You can grab the DSI Utilities from Maven Central. Otherwise, you have to install the .jar file coming with the distribution and the dependencies, which are gathered for your convenience in a tarball.