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

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The discussion centers on troubleshooting image display issues in a Java application using Swing components. Users reported that images specified in JLabel constructors were not appearing in the JPanel. Key solutions included confirming that the images folder is located in the same directory as the compiled class files and using absolute paths to verify working directory issues. Additionally, users highlighted the importance of ensuring that class names and file paths match to avoid NoClassDefFoundError exceptions.

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Nylex
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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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Did you add those 3 lines to Welcome.java?

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

What .jar file?
 
I would use an absolute path to double check that is not a working directory problem. That would at least eliminate one possibility.
 
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?
 
Well there you go. Your working directory is not what you think it is !
 
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>
 

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