This option might be improved a little by using.

````
@Args4jOption(required = false, name = "-output", metaVar = "DIRECTORY", usage = "Directory to generate the comparison output files")
````

In the help output, it will look like..

````
-output DIRECTORY                         : Directory to generate the comparison
                                          output files
````

Instead of..

````
-directory VAL                         : Directory to generate the comparison
                                          output files
````