Java Package Does Not Exist Error

Just reimport didn't work. Following worked for me.

File -> Invalidate Caches /Restart

Then

Build -> Rebuild Project

That will reimport maven project.

Are they in the right subdirectories?

If you put /usr/share/stuff on the class path, files defined with package org.name should be in /usr/share/stuff/org/name.

EDIT: If you don't already know this, you should probably read this doc about understanding classpath.

EDIT 2: Sorry, I hadn't realised you were talking of Java source files in /usr/share/stuff. Not only they need to be in the appropriate sub-directory, but you need to compile them. The .java files don't need to be on the classpath, but on the source path. (The generated .class files need to be on the classpath.)

You might get away with compiling them if they're not under the right directory structure, but they should be, or it will generate warnings at least. The generated class files will be in the right subdirectories (wherever you've specified -d if you have).

You should use something like javac -sourcepath .:/usr/share/stuff test.java, assuming you've put the .java files that were under /usr/share/stuff under /usr/share/stuff/org/name (or whatever is appropriate according to their package names).

I was having this problem, while trying to use a theme packaged as .jar in my app, it was working while debugging the app, but it didn't when building/exporting the app.

I solved it by unzipping the jar, and manually add its contents to my build folder, resulting in this:

project/
   │
   ├── build 
   │   └── classes
   │       ├── pt
   │       │   └── myAppName ... 
   │       └── com
   │           └── themeName ...
   ├── src
   └── lib

I don't have the error anymore and my app loads with the intended theme.

You need to have org/name dirs at /usr/share/stuff and place your org.name package sources at this dir.