NullPointerException charset is null with .jar in Unity 5

Hello, I currently have a .jar library I need to use in Unity along in C#. Unfortunately, that library is not given in C# natively (it is however also given in C). After surfing the internet for a bit, I found something called IKVM which lets you convert .jar libraries into .dlls for use. Thus, I moved my now converted .dll as well as the IKVM .dll's into the Plugins folder. Additionally, I followed the library's tutorial here (in Java): http://www.unidata.ucar.edu/software/thredds/current/netcdf-java/tutorial/NetcdfFile.html

to use the library. It works perfectly in pure Java. However, when I do the same thing in Unity and run the game, an error always occurs whenever I try to read the file: "NullPointerException: charset is null".

Here is the script for reference (It's attached to the appropriate Plane object and ucar.nc2 is the library):

 using UnityEngine;
 using System.Collections;
 using ucar.nc2;
 using System.IO;
 
 public class PlaneScript : MonoBehaviour {
 
     // Use this for initialization
     void Start () {
         string fileName = Application.dataPath + "/Resources/snofh.nc";
         //NetcdfFile ncFile = null;
         //ncFile = NetcdfFile.open("C:\\Users\\mughi\\Documents\\wgrib2\\snohf.nc");
         NetcdfFile ncFile = null;
         try {
             ncFile = NetcdfFile.open(fileName);
         } catch (IOException ioe) {
            Debug.Log("trying to open " + fileName);
         } finally {
             if (null != ncFile) {
                 try {
                     ncFile.close();
                 } catch (IOException ioe) {
                     Debug.Log("trying to close " + fileName);
                 }
             }
         }
     }
     
     // Update is called once per frame
     void Update () {
     
     }
 }
 

The error occurs precisely at the first IOException catch. Can anyone please give any insight into why the error is occurring/what it means?

Thank you!