I have a Java Project in NetBeans 7.0.
I want to add some image to some label dynamically. The image will differ depending on the state of the program.
I put one such image, 'filling.jpg', in the 'resources' folder of my project.
I want to reach this file correctly (not by absolute or relative path, because that will cause problems when I build the jar file).
So I found this method:
ImageIcon fillingIcon = new ImageIcon(getClass().getClassLoader().getResource("filling.jpg"));
labelFontFilling.setIcon(fillingIcon);
It keeps give me java.lang.NullPointerException.
But I am sure that there is that image, because I can assign the image to the label from the NetBeans Properties menu for that label (but I don't want this, I want to add the image by Java code).
What am I doing wrong, and how can I get that image correctly?
This was a pain, using netBeans IDE 7.2.
You need to remember that Netbeans cleans up the Build folder whenever you rebuild, so
Add a resource folder to the src folder:
(project)
src
project package folder (contains .java files)
resources (whatever name you want)
images (optional subfolders)
After the clean/build this structure is propogated into the Build folder:
(project)
build
classes
project package folder (contains generated .class files)
resources (your resources)
images (your optional subfolders)
To access the resources:
dlabel = new JLabel(new ImageIcon(getClass().getClassLoader().getResource("resources/images/logo.png")));
and:
if (common.readFile(getClass().getResourceAsStream("/resources/allwise.ini"), buf).equals("OK")) {
worked for me. Note that in one case there is a leading "/" and in the other there isn't.
So the root of the path to the resources is the "classes" folder within the build folder.
Double click on the executable jar file in the dist folder. The path to the resources still works.
I have a slightly different approach that might be useful/more beneficial to some.
Under your main project folder, create a resource folder. Your folder structure should look something like this.
Project Folder
build
dist
lib
nbproject
resources
src
Go to the properties of your project. You can do this by right clicking on your project in the Projects tab window and selecting Properties in the drop down menu.
Under categories on the left side, select Sources.
In Source Package Folders on the right side, add your resource folder using the Add Folder button. Once you click OK, you should see a Resources folder under your project.
You should now be able to pull resources using this line or similar approach:
MyClass.class.getResource("/main.jpg");
If you were to create a package called Images under the resources folder, you can retrieve the resource like this:
MyClass.class.getResource("/Images/main.jpg");
Thanks, Valter Henrique, with your tip i managed to realise, that i simply entered incorrect path to this image.
In one of my tries i use
String pathToImageSortBy = "resources/testDataIcons/filling.png";
ImageIcon SortByIcon = new ImageIcon(getClass().getClassLoader().getResource(pathToImageSortBy));
But correct way was use name of my project in path to resource
String pathToImageSortBy = "nameOfProject/resources/testDataIcons/filling.png";
ImageIcon SortByIcon = new ImageIcon(getClass().getClassLoader().getResource(pathToImageSortBy));
For me it worked like I had images in icons folder under src and I wrote below code.
new ImageIcon(getClass().getResource("/icons/rsz_measurment_01.png"));
Related
im fairly new to java and im making a pokemon style game for practice and i would like to be able to send the game to my friends.
here is the main problem: the game works fine in my netbeans IDE, but using the jar file in my dist folder does not work and throws a nullPointerException. i have narrowed down the problem. my game uses imageIcons and png/gif images that i have imported in my libraries. im getting access to them like this
Icon bckground = new javax.swing.ImageIcon(getClass().getResource("/pictures/BG.gif"));
i am unsure how to get the images into the lib folder for the program to find. i have tried copying the files straight into the lib folder and creating a folder for them called pictures; neither worked. right now the lib folder contains only a single jar from one of my other libraries. (that is the only jar file that i am importing to my libraries)
Pic of what it looks like in IDE
In my case, i did something like this.
final BufferedImage image = ImageIO.read(new File("something.jpg"));
I just transferred something.jpg into the dist folder, and it worked fine.
After clean-building your project, put the BG.gif into the dist folder, then run your jar file in dist folder. Now everything should be fine. When sending your game to your friends, you can encapsulte (hide, set read-only) your code (google encapsultaion java), then with the BG.gif being transferred into dist folder, archive the project. Then your friends only need to unzip it and find jar file in dist folder.
Hope this will help:)
Please put your picture (BG.gif) in the package (directory) where it is used as icon Icon bckground = new javax.swing.ImageIcon(getClass().getResource("BG.gif")); inside the jar file. You need to change the path of the file first getResource("BG.gif") and then create the jar file from IDE. If the jar does not contain the image, you can open the jar using using any unzip application (winrar etc.) and copy and paste the the image file in the directory where the class is present. Please let me know the outcome.
I'm a teacher attempting to use the AP Computer Science Picture Lab activity. Here are the teacher instructions:
Students should keep the images folder and the classes folder together in the pixLab folder.
The FileChooser expects the images to be in a folder called images, at the same level as the classes folder.
If it does not find the images there it also looks in the same folder as the class files that are executing.
If you wish to modify this, change the FileChooser.java class to specify the folder where the pictures are stored. For example, if you want to store the images in “r://student/images/,” change the following line in the method getMediaDirectory() in FileChooser.java:
URL fileURL = new URL(classURL,"../images/");
And modify it to
URL fileURL = new URL("r://student/images/");
I have created a GitHub repo for them to fork and use in Eclipse, but I'm having trouble getting the images in the right place for Eclipse to see them. Where should they be in the Eclipse Package Explorer? The tree now is:
PixLab > src > default package > various classes.
At what level should I drag and drop the images folder into?
Alternatively, what should I the following line to read?
URL fileURL = new URL(classURL,"../images/");
I'm wondering if there is some confusion between the naming of the project in Eclipse with the folder name for the source files.
The directory structure that you give does not include a pixLab folder. I'd be expecting something more like the following in Eclipse:
PixLab > src > pixLab > various classes
> images > various images
Then, the line:
URL fileURL = new URL(classURL,"../images/");
makes sense, as you are going up one level from the classes folder, and down from there to the images folder.
For the reference to a "student" folder, I think they are considering the scenario where the images are stored in a shared network file folder. In that case, they would NOT be part of the Eclipse package, and the FileChooser Url would have to be modified to reflect your chosen network location for the images.
If you've already set up the project in Eclipse with the "default package", can I suggest doing the following:
From within Eclipse:
1) make a package, named pixLab
2) drag & drop files from the default package to the new package
Eclipse should automatically add the following line to the top of all the source files that you brought over:
package pixLab;
3) place the images folder under src, parallel to the pixLab package.
A "package" functions as a folder. If everything is in the same folder, then the rest of the code should work fine.
Thanks for the attempt, but I'm afraid Java still can't find the jpg images. I'm afraid I'm not yet allowed to post images, but I took a screenshot, and the files are laid out exactly as suggested above. Any other ideas, anyone?
I can't seem to get this right...
I have a Java project in Eclipse called MyProject. In its root is the folders bin, src, and resources. Inside of resources, I have an image named myImage.gif.
In my code, I want to use this image, and I want it to work whether or not this is running from a Jar file. I currently am doing this
ImageIcon j = new ImageIcon(getClass().getResource("/resources/myImage.gif"));
but it is spitting out a null when I run it through Eclipse (not as a Jar).
What is the right way to do this?
If you were to tell Eclipse to treat resources as a source folder then you should be able to say
ImageIcon j = new ImageIcon(getClass().getResource("/myImage.gif"));
When you come to build the JAR you'll have to ensure that the contents of the resources directory go into the top level of the JAR file in order for the same path to work in the JAR case, i.e.
META-INF
MANIFEST.MF
com
example
MyClass.class
myImage.gif
Alternatively, and probably the more common Java idiom, put the image file in the same directory as the .java file (src/com/example in this case) and then use getResource without the leading slash
new ImageIcon(getClass().getResource("myImage.gif"));
Class.getResource resolves a relative path like that against the package of the class in question. Again, you need to have the same structure in the JAR when you come to build that, this time with myImage.gif under com/example.
Place resources into src and Eclipse will copy it into bin.
ImageIcon ii =
new ImageIcon(
ImageIO.read(
getClass().getClassLoader().getResourceAsStream(
"resources/myImage.gif" )));
Without / before the path.
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.
I'm exporting a simple java project that includes two directories; src and Icons. Icons is a directory that contains three .png files.
I'm exporting to an executable .jar file using File -> Export. The export works properly and the .jar file contains the Icon directory. But I can't get the correct path for the .png files when the project is deployed. During the development I'm using the following path:
Icons/picture.png
and it works as long as I run from within the Eclipse IDE.
How do I get the correct path for the icons?
Your code is looking for the image outside of the .jar file. Try the URL constructor of ImageIcon instead.
Icon icon = new ImageIcon(getClass().getResource("Icons/picture.png"));
See Class.getResource().
mmyers is correct, but be aware that getClass().getResource() will load resources relative to the package where the class is defined. I suspect your icons are packaged at the root of the jar file and not relative to the class itself. To get resources from the root of the classpath, try:
getClass().getClassLoader().getResourceAsStream("Icons/picture.png")