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Unable to locate a file in java project running in a executable jar

Both class.getResource(FILE_NAME) and class.getClass().getClassLoader().getResource(FILE_NAME) run perfectly inside my eclipse but the same code getting failed to locate the file which is inside the jar file, when run as an executable jar in windows machine.
I have gone through all related links available for this problem (well, not exactly the same issue but 90% in sync), asked for solution but no reply came from any of those posts, so I'm posting my issue as a separate question hoping for help on this.
In total, 4 cases I have ran to resolve but none worked so far and I'm out of ideas now.
class.getClass().getClassLoader().getResource("/resources/readme.txt");
class.getResource("/resources/readme.txt");
class.getClass().getClassLoader().getResource("resources/readme.txt");
class.getResource("resources/readme.txt");
Ouf of all the above 4 cases, only 2 cases ran successfully in eclipse which are as mentioned below.
class.getResource("/resources/readme.txt");
class.getClass().getClassLoader().getResource("resources/readme.txt");
The other 2 cases just throwing me Exception in thread "main" java.lang.NullPointerException
Coming to the executable jar, all 4 cases are throwing me the Exception in thread "main" java.lang.NullPointerException.
So I have created a folder named resources where my jar is residing and placed my files inside this folder and ran the jar. Now the jar is running without any issues referring to the files inside the resources folder I created. So wherever I run this jar (windows, linux etc.,) I need to create a resources folder and place my files under the folder. Now the question is, can it be possible to make my jar refer the resources folder which is inside the jar itself?
Any help on this is much appreciated!

To get your txt file:
File yourFileIsHere = new File("resources/readme.txt");
Where put your file?
In the same location of your jar, example:
myapp/yourjar.jar
myapp/resources/readme.txt
If you want read file inside of your "src" folder:
InputStream yourInputStream = new YourClass().getClass().getClassLoader().getResourceAsStream("readme.txt");

If you are using Spring:
org.springframework.util.ResourceUtils.getFile("classpath:readme.txt")
Otherwise:
import com.google.common.io.Resources
byte[] byteSource = Resources.asByteSource(Resources.getResource("readme.txt")).read()

method class.getClass().getClassLoader().getResource() may take 3 prefixes: url:, classpath: and file: each prefix tells what is your base of search. If you want to search inside your jar use classpath: prefix. That tells your classloader to search everywhere within your classpath. Here is one example how to deal with it with Spring tools. Look also at ResourceLoader class in Spring

JAR file behaving differently in a different place in file system

I have project called test in Eclipse which I want to export into Runnable JAR file. During the process of exporting the project, when I choose as a location of JAR file the subfolder of test folder in file system, such as C:/.../test/App.jar, it will work. However, when I want to put it for example on my desktop, it will run but in a very limited look (some GUI components missing) and it throws a lot of exceptions saying something like that:
at java.awt.EventDispatchThread.run(Unknown Source) xception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: Could not initialize class com.sun.opengl.impl.windows.WindowsGLDrawableFactory
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at javax.media.opengl.GLDrawableFactory.getFactory(GLDrawableFactory.java}
What can be the problem? I assume it is not good that I have to specify my JAR file concretely into one folder in file system, it would become unuseful for any other potentional user.

Looks like the jar needs other jars to execute. In this case you would have to set the classpath before you execute the jar
This might help you with your problem.

JavaFX 2 - Can´t import .css File

I´m currentl trying to get into JavaFX 2.0 but I can´t get .css Stylesheets to work within my application. I´ve followed the guide at http://docs.oracle.com/javafx/2/get_started/css.htm#BABBGJBI but whenever I try to import a .css file via
scene.getStylesheets().add(Login.class.getResource("loginform.css").toExternalForm());
I get the following Error:
Exception in Application start method
Exception in thread "main" java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:399)
at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:47)
at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:115)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
at Login.start(Login.java:68)
at com.sun.javafx.application.LauncherImpl$5.run(LauncherImpl.java:315)
at com.sun.javafx.application.PlatformImpl$4.run(PlatformImpl.java:174)
at com.sun.javafx.application.PlatformImpl$3.run(PlatformImpl.java:141)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:29)
at com.sun.glass.ui.win.WinApplication$2$1.run(WinApplication.java:62)
... 1 more
The css path is located in my eclipse project path:
C:\Users\UserName\Dropbox\Documents\Eclipse\FirstExamples\loginform.css
I´d appreciate any help, I can´t get it working, not with absolute paths nor with relative ones like shown in the example.

Check the compiled output path of your eclipse project and ensure that loginform.css is in the same directory as Login.class
I´ve solved the problem by putting stylesheets into my src folder not
a very nice solution but going up by ../formm.css doesn´t seem to work
dunno why
You are requesting the css file via the class.getResource method, which will look for the resource in the same location the class is located. When you put the stylesheet in your src folder, then whatever build system you are using is copying the stylesheet to the same directory as Login.class during the build. When you don't place it in that src folder, then the copy is not occuring.
If you don't want to place the css file in the same directory as your Java source, then either set your build system up to copy it across from another directory OR don't use the classloader mechanism when you add a stylesheet, e.g. use an absolute file or http url or a file url based on the user.dir system property (current working directory) instead.
Really though, just placing leaving the stylesheet in the src folder and accessing it in the manner you are doing is fine and it also makes resource location easy when you deploy the app to different environments.

If you use anything as a resource, you have to prefix the name of it with "/" and that resource has to be on the classpath.
I have the setup with a directory e.g. resources, which contains the .css. Then I use this:
scene.getStylesheets().add(Login.class.getResource("/loginform.css").toExternalForm());
The directory 'resources' which contains the .css file is added to the classpath (in Eclipse, for example, just make it be a source folder).
It is however pity that the exception is totally useless; I've noticed that the .css was the problem when I added it for the first time.

Add images to jar

I want to set icon to my JFrame. I do the following:
Image icon = Toolkit.getDefaultToolkit().getImage("src/images/icon.jpg");
this.setIconImage(icon);
It works fine when I run this code from netbeans, but when I try to run this code from jar file, images are not shown in my JFrame. I have tried to load images as resources:
this.setIconImage(Toolkit.getDefaultToolkit().getImage(getClass().getResource("/src/images/icon.jpg")));
but when I run this code it fails with NullPointerException
Uncaught error fetching image:
java.lang.NullPointerException
at sun.awt.image.URLImageSource.getConnection(URLImageSource.java:99)
at sun.awt.image.URLImageSource.getDecoder(URLImageSource.java:113)
at sun.awt.image.InputStreamImageSource.doFetch(InputStreamImageSource.java:240)
at sun.awt.image.ImageFetcher.fetchloop(ImageFetcher.java:172)
at sun.awt.image.ImageFetcher.run(ImageFetcher.java:136)
How can I do this work?
edit:
Thanks to all,
the problem was solved by specifying image as
Toolkit.getDefaultToolkit().getImage(getClass().getClassLoader().getResource("images/icon.JPG"))
As for it seems rather weird, and would be better if it was like
this.setIconImage(new ImageIcon(pathToIcon).getImage());

Assuming your JAR file has a top level directory called images, you can use either:
getClass().getResource("/images/icon.jpg") or
getClass().getClassLoader().getResource("images/icon.jpg")

Looking at the source code of URLImageSource, it appears that the reason that getConnection throws an NPE is that it has a null for the url. And that leads me to suspect that
getClass().getResource("/src/images/icon.jpg")
is returning null. It would do that if it could not locate a resource with that pathname.
I bet that the problem is that you've got the path wrong.
To prove / disprove this, you should run jar tvf on the JAR file, and look for the line that matches "icon.jpg". Is the corresponding pathname the same as what you are using? If not, use the pathname from the matching line in the getResource call and it should work. Alternatively, if the file doesn't show up at all, look at the NetBeans build configs that tell it what to put in the JAR file. (I'm not a NetBeans user, so I can't say where you would need to look ...)
If that leads you absolutely nowhere, another possibility is that getClass().getResource(...) is using a classloader that doesn't know about the JAR file containing the image. (This seems pretty improbable to me ...)

getResource() loads a resource from classpath, not an OS path, and the after compilation your classpath will not include the /src folder, but rather just its contents. So you'd better try /images/icon.jpg.
Also you may find this discussion somewhat useful.

This should do it assuming you can import javax.imageio.ImageIO:
Image icon = ImageIO.read(this.getClass().getResource("/src/images/icon.jpg"));
this.setIconImage(icon);

.."/src/images/icon.jpg"..
The '/src' prefix of the address seems suspicious. Many apps. will provide separate 'src' and 'build' directories, but it normally ends up that the 'src' prefix is not used in the resulting Jar. I recommend trying..
.."/images/icon.jpg"..
& also triple checking that the image is in the location of the Jar that the code is expecting to find it.

For this to work, you should access the images from a directory relative to some fixed class.
For example, if the image files are saved in a directory "images" on the same level as the Toolkit.class, then
this.setIconImage(Toolkit.getDefaultToolkit().getImage(Toolkit.class.getResource("images/icon.jpg")));
should work.

You can simply create a package inside the main source, and incluse your images in this package. Then, just call the images in your main class like:
ImageIcon a = new ImageIcon(MainClass.class.getResource("/Package/Image.jpg"));

JFrame f = new JFrame("Edit Configure File");
//Image image = ImageIO.read(getClass().getResource("images/ctx.Icon"));
f.setIconImage(new ImageIcon("images/ctx.PNG").getImage());//this works for me finally
//f.setIconImage(image);
//f.setIconImage(Toolkit.getDefaultToolkit().getImage(getClass().getResource("images/ctx.PNG")));

Images are not displaying in jar but displaying in compiler?

I know, I know, this has been asked before. But every resource I've looked at uses IconImages while I just have plain Images.
Is there a different solution? Please help as I've been stuck researching and trying to figure this out for days now with no progress.
Image Floor = Toolkit.getDefaultToolkit().getImage("Floor.PNG");
EDIT: If I was to make sure the jar wouldn't compress and I created a seperate directory in the jar for images and put the correct file path, would this code work?

Toolkit#getImage(String s) looks for a file and likely your image is in the Jar and is now a resource not a file. Look to using resources for this.
Note that ImageIO.read(...) can accept an InputStream parameter the Class class has a method, getResourceAsStream(...) which can put the resource into a Stream that ImageIO can read. Give that a try.
Also, are you getting any error messages when you try what you're doing?

Make sure you know what your current directory is, and how it relates to the position of the files in your jar.
Here's how I would handle it.
1) Require there to be a file called "images.txt" in the directory with your jar (or bundle it into the jar.)
2) Make a file called "images.txt" with a format like `FLOOR:C:\\images\\floor.png`
3) Load this file into memory on load.
4) Load your images based on the entries in the file
This will give you the advantage of changing your images without changing your code if it's defined outside the jar :)
It's not loading because you're not putting the path to the images in the declaration. It expects the images to be wherever the jar is (notice there's no directories there)
You need to offload the definition of the file names to a file, or at the very least guarantee the relative position of the files.
Another good option is to put the images in the jar itself, say in an img directory, and reference them there. But then changes to the images require a new jar, which may not be desired for development purposes.

The getImage call is looking in the file system working directory, not inside the Jar file. This is why the jar file loads the images successfully when they are placed in the same directory outside the jar file. If the images are bundled in the jar file, they are no longer file system files to be accessed, but rather Jar file resources. There is a different way to load these, but sorry, I don't know it off the top of my head.

Check the extension of files. I had this problem because the extension was "PNG", when I changed it to "png", everything was ok.

You can't expect a JAR file to magically know where your images are. If you put a JAR file alone on the desktop, it's going to look for the files on the desktop! The code
getImage("Floor.png")
searches the current directory of the JAR (or source project) by default and you'd expect that if the JAR was in the same directory, it would work. If the JAR is on the desktop how does it know where Floor.png is? Of course, you can specify a hard-coded path
getImage("C:\Some Folder Path\Floor.png")
but then Floor.png has to be in C:\Some Folder Path\ for the JAR to work properly.
It sounds like what you really want to do is keep the images in the JAR file (which acts like a ZIP file). The tutorial on doing that is here:
http://download.oracle.com/javase/tutorial/uiswing/components/icon.html#getresource

And I know for ImageIcon you use: new javax.swing.ImageIcon(getClass().getResource("myimage.jpeg") but I have not found anything similar for plain Image.
<head-desk /> You should really get into reading the JavaDocs. Otherwise you are 'coding by magic'. Which generally won't work.
URL urlToImage = getClass().getResource("myimage.jpeg");
// If you need to support Java 1.3
Image image = Toolkit.getDefaultToolKit().getImage(urlToImage);
// If your users have dragged their JRE into this millennium
BufferedImage bufferedImage = ImageIO.read(urlToImage);