Thread: Illegal Argument Exception: input == null

So, I'm creating a card game. To create the background image I create a level class from a bunch of different tiles. These tiles are selected from scanning a .png image: depending on the colors of the pixels of the image, the level tiles are selected.

I'm developing this in Eclipse, and running it from there has never been a problem.

However, when I tried exporting it as a runnable jar I couldn't start it by clicking it. So, I tried running it through windows command prompt instead. My program didn't run now either, but I got the following readout in the command prompt:

D:\The Documents\Programmering\Project\ProjectAI>java -jar ProjectAI1.jar
Exception in thread "main" java.lang.IllegalArgumentException: input == null!
        at javax.imageio.ImageIO.read(Unknown Source)
        at org.geec.bluffai.level.Level.loadLevel(Level.java:40)
        at org.geec.bluffai.level.Level.<init>(Level.java:26)
        at org.geec.bluffai.graphics.Screen.<init>(Screen.java:23)
        at org.geec.bluffai.Coordinator.<init>(Coordinator.java:35)
        at org.geec.bluffai.Starter.main(Starter.java:10)

I then went to check my loadLevel method and it looked like this: [Java] Loadlevel first - Pastebin.com (Note that I do not know really anything about the try-catch block or exception-throwing in general.)

I did some google searches and changed my catch statement to

catch (IllegalArgumentException | IOException e)

so that my loadLevel method now looks like: [Java] Loadlevel second - Pastebin.com

I then exported it as a new executable jar and ran it again. This time it started. However, when using the command prompt to run it I got these readouts:

D:\The Documents\Programmering\Project\ProjectAI>java -jar ProjectAI2.jar
[ERROR] Can't load level.
java.lang.IllegalArgumentException: input == null!
        at javax.imageio.ImageIO.read(Unknown Source)
        at org.geec.bluffai.level.Level.loadLevel(Level.java:40)
        at org.geec.bluffai.level.Level.<init>(Level.java:26)
        at org.geec.bluffai.graphics.Screen.<init>(Screen.java:23)
        at org.geec.bluffai.Coordinator.<init>(Coordinator.java:35)
        at org.geec.bluffai.Starter.main(Starter.java:10)
[ERROR] Can't load level.
java.lang.IllegalArgumentException: input == null!
        at javax.imageio.ImageIO.read(Unknown Source)
        at org.geec.bluffai.level.Level.loadLevel(Level.java:40)
        at org.geec.bluffai.level.Level.<init>(Level.java:26)
        at org.geec.bluffai.graphics.Screen.<init>(Screen.java:23)
        at org.geec.bluffai.Coordinator.start(Coordinator.java:43)
        at org.geec.bluffai.Starter.main(Starter.java:12)

While the game is now runnable, the problem is still there. I would want to fix this but I do not know how to, as I do not know why I'm receiving these errors while running the game as an executable, but not while running it in Eclipse. As such I wonder if anyone have any idea of what the cause could be or how I could fix it?

The weird thing is that the .jar does work after I added the extra "catch" part after the ImageIO.read() so while it does indeed seem like my path would not be valid when I've exported the jar, it must be, as the proper image is read in, it just throws an exception first.

I've been trimming away code to create an SSCCE for a bit now, however I have yet to create anything that would make sense as an SSCCE without actually creating a new program from scratch (I could do that but then everything works flawlessly). Hopefully I can get something up soon though.