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My resource does not load - "Input stream must not be null"

I read ~4 Stackoverflow Posts (1, 2) already, and did everything like it was explained there, but I get a NullPointerException while I try to load an Image.
Exception in thread "JavaFX Application Thread" java.lang.NullPointerException: Input stream must not be null
My package structure:
Code where I try to load the image:
Image image = new Image(this.getClass().getResourceAsStream("/regexgolf2/ui/img/edit.png"));
I don't understand why It does not work.

Your images are in a package under the src folder. The class loader does not look there for files. The class loader looks for files in your class path.
In order for getResource to work in your case, you need to put the images in the class path.
I suggest you copy the image files manually to your build folder (under the same path, e.g. out/regexgolf2/ui/images and run your app again.
If it works you can start thinking of ways to get the files to the class path (e.g. copy them as part of the build/packaging process or putting them in another folder which is in the class path).

In the case of a netbeans maven javaFX project, the resource (img folder) must be in the resources folder:
Then you can load the resource, for example:
Image escribir = new Image(getClass().getResourceAsStream("/img/login.png"));

I have similar problem in IntelliJ, all look fine but didn't work. In my case, When I rebuild project, all work correct.

I had the same problem in IntelliJ , I wanted to show Image in ImageView on button click and this was a solution for me, don't use getClass().getResourceAsStream("imagePath");
Image image = new Image(String.valueOf(new File("/images/image3.png")));

You can try:
URL url = ClassLoader.getSystemClassLoader().getResource("img/pic.jpg");
Image imProfile = new Image(url.openStream());
ImageView profileImage = new ImageView(imProfile);

Image not loading in jar file

I am trying to fix this problem. Trying different solutions but nothing works. I am using NetBeans IDE. I created a project with this structure and files:
E:\java\project\ecadpb\src\ecadpb
The image files are in
E:\java\project\ecadpb\src\
I have specified working folder for my project in Netbeans as E:\java\project\ecadpb
I have created my image icons like this
new ImageIcon("device21.png");
In my source file, it works perfectly while running the project in Netbeans but images are not showing up when I build and run my JAR file separately. But the image files are inside the JAR.
I have also tried the answers for the same question asked previously.
URL imageUrl=getClass().getResource("device21.png");
new ImageIcon(imageUrl);
But it doesn't work in my case. I am building a JAR file for the first time. Can anyone help me with this!!

A simple way of doing this will be to add the image in your classpath or a directory in your classpath say img as shown below:
E:\java\project\ecadpb\src\main\java\img\device21.png
And then load your image from this location like this:
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
URL resource = classLoader.getResource("img/device21.png");
ImageIcon icon = new ImageIcon(resource);

Create a source folder called Images (ie if you're using eclipse, right-click your project -> new ->sourceFolder). Call it whatever you want, i called my Images. Put some images in it.
Now i had JLabels where i gave them ImageIcons. Look at the following code.
ImageIcon BPawn;
ImageIcon WPawn;
JLabel Label = new JLabel[8][8] //2D array of labels that gives each spot a position.
public void setPieces(){
//set up pawns in their respective positions.
BPawn = new ImageIcon("Images/BPawn.png", "BPawn");
WPawn = new ImageIcon("Images/WPawn.png", "WPawn");
for(int i=0;i<Label[0].length;i++){
Label[1][i].setIcon(BPawn);
Label[6][i].setIcon(WPawn);
}//end for
}//end setPieces.
There is a lot more in setPieces() method, but this glimpse is how you would reference the images in your source folder when you create an executable jar and want the images to show up.

I think answer could be one these suggestions here

I have used a similar approach,
a) Specify the package path to the image file name.
b) Make sure that the image file is not ommited by your build scripts and that it is present in your jar file.

Why is my BufferedImage receiving a null value from ImageIO.read()

BufferedImage = ImageIO.read(getClass().getResourceAsStream("/Images/player.gif"));
First of all, yes I did add the image folder to my classpath.
For this I receive the error java.lang.IllegalArgumentException: input == null!
I don't understand why the above code doesn't work. From everything I read, I don't see why it wouldn't. I've been told I should be using FileInputStream instead of GetResourceAsStream, but, as I just said, I don't see why. I've read documentation on the methods and various guides and this seems like it would work.
Edit: Okay, trying to clear some things up with regards to what I have in the classpath.
This is a project created in Eclipse. Everything is in the project folder DreamGame, including the "Images" folder. DreamGame is, of course, in the classpath. I know this works because I'm reading a text file in /Images with info on the gif earlier on in the code.
So I have: /DreamGame/Images/player.gif
Edit 2: The line that's currently in the original post is all that's being passed; no /DreamGame/Images/player.gif, just /Images/player.gif. This is from a method in the class ImagesLoader which is called when an object from PlayerSprite is created. The main class is DreamGame. I'm running the code right from Eclipse using the Run option with no special parameters
Trying to figure out how to find which class loader is loading the class. Sorry, compared to most people I'm pretty new at this.
Okay, this is what getClassLoader() gets me: sun.misc.Launcher$AppClassLoader#4ba778
getClass().getResource(getClass().getName() + ".class") returns /home/gixugif/Documents/projects/DreamGame/bin/ImagesLoader.class
The image file is being put in bin as well. To double check I deleted the file from bin, cleaned the project, and ran it. Still having the same problem, and the image file is back in bin

Basically, Class.getResourceAsStream doesn't do what you think it does.
It tries to get a resource relative to that class's classloader - so unless you have a classloader with your filesystem root directory as its root, that won't find the file you're after.
It sounds like you should quite possibly really have something like:
BufferedImage = ImageIO.read(getClass().getResourceAsStream("/Images/player.gif"))
(EDIT: The original code shown was different, and had a full file system path.)
and you make sure that the images are copied into an appropriate place for the classloader of the current class to pick up the Images directory. When you package it into a jar file, you'd want the Images directory in there too.
EDIT: This bit may be the problem:
First of all, yes I did add the image folder to my classpath.
The images folder shouldn't be in the classpath - the parent of the Images folder should be, so that then when the classloader looks for an Images directory, it will find it under its root.

If you use resourceAsStream "/" referes to the root of the classpath entry, not to the root of the file system. looking at the path you are using this might be the reason.
If you load something from some home path you probably should use a FileInputStream. getResourceAsStream is for stuff that you deploy with your app.

Java: NullPointerException from class.getResource( ... )

I was writing a small application and when I tried to create an ImageIcon I always got an exception. The exception was caused by this line of code:
prayerLevel.setIcon(new ImageIcon(getClass().getResource("/icons/icon_prayer.png")));
Now within my program, the folder /icons/ does exist. I don't know if it makes the difference but the class file is within a package, where as the icons folder is within the project folder (when you would see the bin and src folder).
I have looked around for a bit and I couldn't find a solution that could help me solve the problem. Perhaps any of you guys could help?
Edit: someone asked for my folder hierarchy:
I know the class file is not in the same folder as the icons are, but I've made applications where I had to load files from a different folder and doing /folder/ always used to work.
Edit 2:
System.out.println(getClass().getResource("/icons/icon_prayer.png") == null);
Prints true.

I believe the NPE is being thrown from the ImageIcon constructor as getResource is returning null.
Try the following:
getClass().getClassLoader().getResource("/icons/icon_prayer.png")
Or:
ClassLoader.getSystemResource("/icons/icon_prayer.png")

As far as I know getResource() will look into locations of known resources, in other words if the folder /icons/ is not seen as a resource folder it will not as you had expected. There are two ways of going around this as far as I know:
1) Set icons folder as a resource to the application, then you can use getResource() for instance
URL css_url = getClass().getResource("/resource/style.css");
For more info on this option, see http://lj4newbies.blogspot.com/2008/03/using-classgetresource-load-resource.html
2) Get the icon as a regular file without using getResource() method. This is actually adviced in Swing tutorials on Sun/Oracle own documentation .
Generally, applications provide their own set of images used as part
of the application, as is the case
with the images used by many of our
demos. You should use the Class
getResource method to obtain the path
to the image. This allows the
application to verify that the image
is available and to provide sensible
error handling if it is not. When the
image is not part of the application,
getResource should not be used and the
ImageIcon constructor is used
directly. For example:
ImageIcon icon = new
ImageIcon("images/middle.gif",
"a pretty but meaningless splat");
Hope this helps, good luck!

Old thread but since I bumped into a similar problem just now...
I'm using Eclipse and I copied a file to the "resources" folder using system commands (cp). However, eclipse threw a NullPointerException because I didn't refresh the "resources" folder. So the file was there but Eclipse didn't see it.
So in Eclipse: "Package Explorer" -> "resources" -> Mouse right click -> refresh. This fixed it for me.

I added my music, images, etc to a folder added to the build path. Then I just used
URL url="CurrentClass".class.getClassLoader().getResource("media file name not the path");
setIconImage(new ImageIcon(url.getPath()).getImage());
to set the image icon.

The only thing that can throw a NullPointerException in this line of code is the first ., which means that prayerLevel is null.

NullPointerException when accessing image files in a .jar file

I have pretty much tried everything but still have this same problem. I have the following setup: I have a images.jar containing a folder called 'images' in which there are multiple image files. I add images.jar to the java build path of the project in eclipse, and i've been trying to use the following code to access the individual images in the jar:
URL url = this.getClass().getResource("images/a.png");
ImageIcon icon = new ImageIcon (url);
Unfortunately, the URL object is always NULL. I don't think this has anything to do with where I put images.jar file as it is added to the classpath in eclipse. I have also tried using the path '/images/a.png', but still the same problem. Any suggestion would be extremely welcome! Thanks.

Try this:
URL url = this.getClass().getClassLoader().getResource("images/a.png");
ImageIcon icon = new ImageIcon(url);
Without getClassLoader() invocation you are only able to access resources in JAR file where the code is stored.

I couldn't reproduce your problem, but my theory is that you are running the class from a different place than you think you are -- that the image and the class are in different jars, or the class is read directly from the class file.