I used following code to access an image from "res" folder with NetBeans
imgWelcome = Image.createImage("/cover.png");
img = new ImageItem(null, imgWelcome, ImageItem.LAYOUT_CENTER, "");
Though the resource is not getting detected and i keep on getting NullPointerException. As weird as it sounds, exactly same technique worked in my previous program.
What am I doing wrong here?
P.S. I've double checked that the file exists in the res folder
There might be many reasons for this, but I have found that most of the time, it is due to how the project is built. Some build scripts include the resources in the res/ folder as top-level files, and some include that folder as a folder in the jar file.
What I have always done to troubleshoot is to rename the jar output to zip and look inside. If the image files are contained in a folder then you should address them as such.
Your code will not find cover.png if it is in the /res folder.
Inspect the contents of your jar using 7-Zip or similar, ensure the image really is in the /res folder, then replace the first line with imgWelcome = Image.createImage("/res/cover.png");.
Oh wow.. this was because .png was not supported by my emulator. And what all I tried :(
Related
I have tried many variants but I cant find correct.
I have something like
Inside my jar, which created by Maven I can see that
That is my folder with classes. And, by the way, If I start my program in IDEA, not from Console, there is not any exception with paths
Here, I am in debug mode start my jar trying to see, where is the problem.
If I do 'file.exists()' it would be false but file inside. I think, that problem because of '.jar!\' in the path, but I don`t know how to remove that.
Anyway I've tried absolute and relative path, I've tried
Thread.getCurrentThread.getContextLoader.getResource()
GUI.class.getResource()
GUI.class.getClassLoader.getResource()
Nothing help
You can't use File to open resources inside a jar file. File can only be used with normal files and directories.
Note: using File works fine within in the IDE, since all files are not packaged in a jar file yet. But the program will break after you package it.
Once you locate the resource eg. URL res = GUI.class.getResource("/rxtx64/myres.dll") , you can open that resource as a stream InputStream is = res.openStream(); .
See also related answers Utils to read resource text file to String (Java) and How to read a text-file resource into Java unit test?
I've spend 5 hours already and have no idea why images are not loaded when running Jar.
Project structure:
Blackjack_Game
- Source Packages
- Images
- blackjack
.... classes...
At project properties I have src - Source Packages folder added by default. Tried to put images directly into the project's folder and removing /Images/, but still no help.
Inside the code I have:
dealer_url = getClass().getResource("/Images/4_of_hearts.jpg");
File img = new File(dealerCardGenerator.dealer_url.getPath());
BufferedImage bufferedImage = ImageIO.read(img);
dealerCardGenerator.imageIcon = new ImageIcon(bufferedImage);
So inside NetBeans IDE everything is OK. Fully working. But after built&clean I see no images, but all actions are done.
Can you please suggest what is wrong? Getting so mad because of this ((((
A jar entry is not a file. java.io.File can only identify a file, not a jar entry. java.net.URL however can identify a jar entry using the jar: scheme, or a file using the file: scheme. That's why Class.getResource() returns a URL not a File.
Two solutions:
use the URL: ImageIO.read(getClass().getResource("whatever"))
ImageIO can also use an already-opened stream, which classloader can provide:
ImageIO.read(getClass().getResourceAsStream("whatever"))
Duplicate of at least #2-4 of the questions autosuggested as related:
Including Images with an executable jar
Loading images in a jar
Getting images from a .jar file
Thank you all for clarifying the problem. I've realized why some functions were not working.
So the solution is to replace URL with ImageIcon:
ImageIcon i2 = new javax.swing.ImageIcon(getClass().getResource("whatever"));
and then just set icon as label icon:
jLabel1.setIcon(i2);
In this way JAR works. Previously, all methods after this icon set operation were not working, as the program was actually stopped, now everything works fine.
I have this project structure:
ProjectName
src
xxx
co
com
package
something.java
web
image
print
pic.jpg
I want to load the pic.jpg in the java file which will then be used in the pdf file generated. I have gone through the answers here but, nothing helped me yet. Possibly I am missing a small thing.
If the pic.jpg was under package, then getClass().getResource("pic.jpg") works absolutely fine. getClass().getResource("/web/image/print/pic.jpg") doesnt work as well. But I want to place all my images under image folder and refer it in the java file.
You should get the application runtime path and rebase the path to the folder which images locate.
You can use the code:
String path = new File(".").getCanonicalPath();// or System.getProperty("user.dir")
Seems your files are not copied to bin/ directory. Change your build script to copy them to output directory
getClass().getResource() will use class loader to load class, since those files need to be in classpath
I want to get the path to a resource for ImageIO to read out a BufferedImage from some .png s.
While developing the project I use a relative path to "/bin/stuff/icons/image.png" , but this will definetly not work when I put everything together into a .jar file, so I need a way to get the path to these resources both while testing in eclipse and when later running it within a .jar .
After a lot of trying out both finding the file and getting the input stream to the file I came to the conclusion that this approach works every time:
InputStream in = ClassLoader.getSystemClassLoader().getResourceAsStream(path)
BufferedImage image = ImageIO.read(in)
Where path is
"projectName/resourceFolder/" + nameOfResource.stuff
as found in the src directory of the eclipse project.
E.g.
"myProject/images/icon.png"
When getting only the resource and then getting the path of the resource to link to a file, you will get FileNotFoundExceptions when using a .jar (but not while testing with eclipse, so one should be warned to think that his code works).
And - no - I don't save images in the bin/ - but they are copied to this directory and thus I find them there while testing. Now everything seems to be working.
Don't put anything under the bin directory in Eclipse: if you run a clean on the project it will be erased.
What you can do is to define a new source folder like resources, and put the image there. This way it will be automatically copied to the bin folder.
If you include the resources folder into the Jar, it will be available in both environments by using something like:
ImageIO.read( getClass().getResource("/image.png") )
PS: You can evade using a different resources folder but mixing the sources and images will quickly pollute your source folder.
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.