help with linked lists or powershell

Question

Im doing some homework.. and im reading in a file through the cmdline and saving each word as a node in a linked list. We have to run the program as a jar file in powershell.
I know nothing about powershell and somehow the prof excpects us to figure it out, fair enough.
I keep gettin a nullpointer exception but i dont know how to de bug in powershell??
Ive looked online but the things i have tried have not helped at all.
So anyone able to give me a hand?

Answer 1

I’m writing in bluej but I’ve never set it up in bluej so that you just send it a file without doing the hasNext and read for each line etc like it is taking in the command line so I don’t know how to run the program in bluej without doing a file input stream?
I’ll post some code

https://code.sololearn.com/cS82mnANo00f/#java

here's a link to the code. I posted all of it cause I don't really know what a person would need to see. There are a few things that don't work but right now I just want to get passed the NullPointerException lol.