Organizing class files (in the filesystem)

Hi, I'm new to Java and the JDC. I have run into one issue, in my explorations in Java, and that is organizing the class files and source code files. I understand that I can organize them in any way that I like, but I was curious if there is a standard system that other Java developers use (like the /usr/local convention on Unix).
Should I create a /usr/local/java directory and then store class and source files in subdirectories of that? And then add the class directory to the CLASSPATH? How about downloaded source code that I didn't write -- that seems like it would then go in yet another directory.
So far I've got everything stored in ~/dev/java (a directory I created for this purpose), but it seems like it's bound to get unmanageable if I don't order it better. And I'm just curious what others with more experience do.
Thanks!
Erik

Anyway, back to why. If as you mentioned you keep all of your class files off a given root folder, then you can add that folder root to the classpath.
Okay, I have the domain "erikprice.com". So then I would create a hierarchy like this (?) :
- ~
- dev
    - Java
      - com
        - erikprice
          - packageA
          - packageB
          - packageC
             ...etc...And then, if I add ~/dev/Java/com to my CLASSPATH, all of the classes in the various packages below that will be accessible to the compiler? Or do I have to explicitly put ~/dev/Java/com/erikprice into the classpath?
Also, if I have downloaded someone else's source code (such as a Jakarta project or something), it seems like I should put its root folder in with my personal root folder. In other words, like this:
- ~
- dev
    - Java
      - com
        - erikprice
      - org
        - apache
          - xml
            - xerces
              - packageA
              - packageB
            - xalan
              - packageA
              - packageB
              ...etc...Does this seem right? If I understand correctly, I will have to add the org directory to the CLASSPATH too. Can I save all of this trouble by putting just ~/dev/Java into the CLASSPATH so that all of the packages below (com/erikprice/*, org/apache/xml/*, org/someotherproject/*) are available?
The trick of this is that I'm trying to organize both my own Java files as well as those that I've downloaded to study from. Thanks for your input, MLangstaff.

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Organizing class files (in the filesystem)

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