Scala/Java subdirectories with dots in names

Question

By some reasons I need to use long names of the packages in my project. Like:

com.example.foo.bar.bazz.anotherlongsubpart.andfinallytheactualpackagname

So considering the name convention(at least what I know about name convention in Java), I have to create appropriate directory structure replacing dots with slashes:

com/example/foo/bar/bazz/anotherlongsubpart/andfinallytheactualpackagname

As for me it looks too ugly :) So I tried instead to replace with slashes only the part of dots:

com.example.foo.bar.bazz.anotherlongsubpart/andfinallytheactualpackagname

In other words I have here one package/directory with long name "com.example.foo.bar.bazz.anotherlongsubpart" and another one with "andfinallytheactualpackagname". Is it legal to do that? I tried to compile all this stuff using Simple Build Tool, and run my unit tests on it. And it works well. As I would name it in more ordinary fashion with slashes.

So as my experiment shows it works well at least with SBT. But I'm not sure whether such practice may lead to further issues? Maybe in different environments with different kind of class loaders etc?

If you're going to do that, you might as well just put your source files directly in `src/main/scala/`. — Chris Martin, Oct 05 '13 at 21:25
Good idea, Christopher, thanks. Well, I use IntelliJ Idea and it marks such things as warnings. Whereas there is nothing bad with example above. It's not a big deal but I prefer to be in good relations with my IDE. :) — Ilya Lakhin, Oct 06 '13 at 16:27
Nah, man, without inspections and other similar stuff I could use vim instead :) — Ilya Lakhin, Oct 08 '13 at 16:12

score 8 · Accepted Answer · answered Oct 05 '13 at 20:14

8

In Scala, the directory name does not have to map to the package declared at the source file, the compiler won't enforce this in any way.

In Java, you can't do that. The source file must be at the correct directory (as dictated by the package name declared a the source file) for it to compile.

So, if you're in Scala, you can do it as much as you like, in Java, no, you can't.

answered Oct 05 '13 at 20:14

Maurício Linhares

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My project is in Scala only. But what about the end class files packed in JARs. Will there be any penalties if I run my jar on various JVMs? – Ilya Lakhin Oct 05 '13 at 20:18
No, it won't make any difference. – Maurício Linhares Oct 05 '13 at 20:19
The Scala compiler will place them in the proper folders inside the JAR. – Alexey Romanov Oct 06 '13 at 12:40
Thanks Alexey, just noticed it too. – Ilya Lakhin Oct 06 '13 at 16:22

score 4 · Answer 2 · answered Oct 05 '13 at 20:14

4

Scala doesn't care what your directories are named, Java does. If you have Java code, follow its conventions. For Scala, do whatever you feel like (including not using package name for directories).

answered Oct 05 '13 at 20:14

Daniel C. Sobral

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dkatzel · Answer 3 · 2013-10-05T20:12:39.690

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I would not recommend doing that. As discussed in the Oracle package name documentation Many tools that need to translate between qualified class names and directory locations will simply replace "." with file separators and your names would break that.

edited Oct 05 '13 at 20:12

answered Oct 05 '13 at 20:03

dkatzel

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There are limits to which I'm willing to obey the instructions of somebody at Sun from 1995... – Chris Martin Oct 05 '13 at 20:14
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@ChristopherMartin This is not "instructions", this is Java rules, as much so as with any syntactical rule of the language. – Daniel C. Sobral Oct 05 '13 at 20:16

Scala/Java subdirectories with dots in names

3 Answers3