Why aren't my images appearing in my Java application?

In summary, the conversation discusses an issue with images not appearing in a JPanel despite the code compiling fine. It is determined that the images must be in the same folder as the classes or their entire paths must be explicitly defined. The conversation also touches on the topic of the interpreter's location and the use of an IDE like Eclipse.
  • #1
Nylex
552
2
Hi, I'm working through the "Building an Application: Part 2: Introduction to Inheritance, Panels, and Layouts" on java.sun.com and the code I've written compiles fine, but the images that are supposed to appear in the JPanel aren't there.

Code:
jl = new JLabel("Java Technology Dive Log", new ImageIcon("images/diveflag.gif"), JLabel.CENTER);

and

Code:
diver = new JLabel("", new ImageIcon("images/diver.jpg"), JLabel.CENTER);

are where images are used.

The image files do exist. They're in a folder called "images", which itself is in a folder named "divelog". The whole code for the file is here, although obviously this class is used in another.

If anyone can help, thanks.
 
Last edited:
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  • #2
Did you add those 3 lines to Welcome.java?

Code:
add(jl, BorderLayout.NORTH);
add(ta, BorderLayout.CENTER);
add(diver, BorderLayout.SOUTH);
 
  • #3
Yep, I did.
 
  • #4
Do you have your images folder and java .jar file in the same directory?
 
  • #5
faust9 said:
Do you have your images folder and java .jar file in the same directory?

What .jar file?
 
  • #6
I would use an absolute path to double check that is not a working directory problem. That would at least eliminate one possibility.
 
  • #7
so-crates said:
I would use an absolute path to double check that is not a working directory problem. That would at least eliminate one possibility.

It works with an absolute path, so what else could be the problem?
 
  • #8
Well there you go. Your working directory is not what you think it is !
 
  • #9
Why's it not the current directory?!
 
  • #10
I believe its usually the directory in which the class file is located, though I could be wrong. Check the documentation on Sun's site: http://java.sun.com.
 
  • #11
Will do, thanks :smile:.
 
  • #12
Actually I think its the directory in which the interpreter is run. How are you running the interpreter?
 
  • #13
so-crates said:
Actually I think its the directory in which the interpreter is run. How are you running the interpreter?

I'm using BlueJ. I'll try from the command line and see if that makes any difference.

Edit: I can't run from the command line. I'm getting:

Exception in thread "main" java.lang.NoClassDefFoundError: DiveLog (wrong name:
divelog/DiveLog)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)

when I try "java DiveLog". The class name is DiveLog, so I don't know what the problem is. It works in BlueJ though :confused:.
 
Last edited:
  • #14
New to the forum here.

I'm having the same problem with the images not being displayed.

Has anyone figured out the cure?

Mike
 
  • #15
The interpreter's location is irrelevant because you can have work-related material in other directories.

A standard IDE for Java such as Eclipse can obviously be in a different location (such as c:\eclipse) and compile things fine from other directories because the compiler KNOWS where to find the standard libraries.

The thing with images is that they have to be in the /same/ folder as your classes, otherwise you have to explicitly define their entire paths.

If it's in a folder, then the folder has to be in the same folder as your main/test class.

If your main class as well as other classes are in let's say, C:\class

then the images should be in C:\class\images\<imageFile>
 

1. Why are my images missing in Java?

There could be several reasons for missing images in Java. One possibility is that the path to the image file is incorrect or the image file does not exist in the specified location. Another reason could be a coding error or a problem with the image loading process. It is important to check the code and make sure the image file exists in the correct location.

2. How do I fix missing images in Java?

The first step to fixing missing images in Java is to check the code and make sure the image file exists in the correct location. If the file is in the correct location, try clearing the browser cache and reloading the page. You can also try using a different image format or resizing the image. If the issue persists, it could be a problem with the Java Virtual Machine or the browser itself, and you may need to update or reinstall these components.

3. Is there a common cause for missing images in Java?

One common cause for missing images in Java is a mismatch between the image file format and the Java Virtual Machine. If the image file is not compatible with the Java Virtual Machine, it may not be able to load the image properly. It is important to use image files that are supported by the Java Virtual Machine.

4. Can a slow internet connection cause missing images in Java?

Yes, a slow internet connection can cause missing images in Java. If the image file is large and takes a long time to load, it may not be able to load properly on a slow internet connection. In this case, it is important to optimize the image file size or improve the internet connection speed.

5. Is there a way to prevent images from going missing in Java?

To prevent images from going missing in Java, it is important to use proper coding practices and make sure the image file exists in the correct location. You can also use a content delivery network (CDN) to host the image files, which can improve the loading speed and reduce the chances of images going missing. Regularly testing and debugging your code can also help prevent missing images in Java.

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