Download
The LEIA project is in its planning phase still. Your best bet on trying the code would be to check out the source code from the LEIA project page on GitHub.
Consult the latest API documentation.
The last distribution is quite out of date. To use it you need to have a Java Development Kit (JDK) installed (in official Oracle terminology: a J2SE SDK). The JDK contains an archiving tool named 'jar' that can be used to unpack the zip file:
jar xvf zip-file
Visit the LEIA project page on GitHub for project details.