Quick Easy One About Packages - Topic

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Sep 29 2012 05:54am

Im using netbeans and have learned that one should not use default package for larger programs.

Have created a package for all .gif files and a package for the logical classes.
Now the program cant even compile in the normal way.

Error message:

Quote

java.lang.NoClassDefFoundError: NewJFrame
Caused by: java.lang.ClassNotFoundException: NewJFrame
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
Could not find the main class: NewJFrame. Program will exit.
Exception in thread "main" Java Result: 1

I can run the NewJFrame by rightclicking and choosing "run file". But now the images cant be seen.

Cant figure out how to import the images to NewJFrame

import programName.imagePackage;
or
import imagePackage;
doesnt work

Any help is welcome

carteblanche

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Sep 29 2012 06:40am

1. images belong in a folder, not a package. as a result, they do not get imported
2. when using the images in a folder, you must reference them by their folder. eg instead of "image1.jpg" you must say "images/image1.jpg" if they're in the images folder
3. that looks like a runtime error to me, not a compile time error
4. what is "the normal way" you run it? using the command line and saying "java NewJFrame"? or is it in a jar file? or something in netbeans? if it's in a jar file, make sure you're using a manfiest which specifies the new package. if it's in netbeans, make sure you set up runtime settings to point to this new package name

tigeranden

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Sep 29 2012 08:00am

ty for help

Quote

if it's in netbeans, make sure you set up runtime settings to point to this new package name

didnt know that, worked fine.

Code

1. images belong in a folder, not a package. as a result, they do not get imported

thought that was kind og the same thing. But "images/image1.jpg" also works.

irimi

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Sep 29 2012 09:02am

Quote (tigeranden @ Sep 29 2012 07:00am)

Code

1. images belong in a folder, not a package. as a result, they do not get imported

thought that was kind og the same thing. But "images/image1.jpg" also works.

a folder can only contain one set of files.

a java package can contain more than one set of classes which, in turn, can be stored in more than one folder.

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