Java 8 is required for running Eclipse with PandionJ.
There are two possible ways for you to try PandionJ, either by installing the plugin in Eclipse, or by dowloading an Eclipse package with PandionJ pre-installed.
PandionJ requires Eclipse Neon (or a more recent version). After obtaining Eclipse, execute it and click "Install New Software..." on the Help menu. The next step is to provide the Update Site URL.
Insert http://pandionj.iscte-iul.pt into the 'Work with' textbox, tick all the options, and proceed with the installation. Upon completion, Eclipse will need to restart. Now you are ready to get started.
These are Eclipse packages (for Java Developers) with the PandionJ plugins already installed. Future updates can be fetched using Eclipse's Check for Updates.
