Question

Is there an appropriate exception class for invalid command line arguments in the Java API or do I have to create my own? I’ve tried searching for one but can’t find any in the API.

This is for an assignment so I cannot use third party libraries for command line parsing.

Answer 1

The best way to handle unknown command line parameters or combinations that don’t make sense to the program is to display an error message and offer a usages output.

Personally, depending on the complexity of the command line, I will create a method called “usage” (usually static) that can have an optional error message passed to it.

While parsing the command line parameters passed into the program, I will call this method and either exit, via a flag or directly, or have usage method call exit for me.

But that’s just me