java - Can I convert eclipse source folders into packages?

Question

I've forked a Github project, used Eclipse to clone it locally, and imported that as a general project into Eclipse. The accompanying .project file is an Eclipse .project file with the proper "nature" and "buildCommand" xml tags. So it seems like a valid Eclipse project. However, I'm unable to specify a run configuration or configure the build path. When I select the Build Path popup menu item, it says "no actions available" in grayed out text. When I select "Run/Run As" from the main menu, it shows (none applicable). I'm wondering if the problem is that the project imported completely as source folders:

There are no packages to speak of. I created another project from scratch, and created the proper source folders and packages as needed to match the package statements in the source code. After manually importing the source from the git repo, I can build and run that project.

If the lack of packages is indeed the problem, is there a quick way in Eclipse to convert source folders to packages?

Answer 1

What you did is you have probably cloned the repo in Eclipse and then Imported this project through a New Project Wizard, because in GitHub there is no existing .project (and no .classpath) files.

The "New Project Wizard" will create a set of defaults for a java project (I suspect that you selected just that), but is anaware of Maven structure, so all source folders will not be recognized and you will end up having to define them on your own. Worse, you will be unaware of any special parts of the Maven build that might be configured within pom.xml.

Because this project uses Maven for building, it would be better to use M2Eclipse while importing it. Install it using Help->Install new software.

Then there are a couple of steps required to make it use all Eclipse features.

Keep your cloned copy of the repository or clone again if you want to start from scratch. Then use File->Import feature to import a maven project into the workspace. Select Exisiting Maven Projects and point to the directory containing pom.xml file in the cloned repo. This will use Maven integration in Eclipse to generate .project and .classpath files based on pom.xml contents, so you will be able to more closely mimic Maven build in Eclipse. All source folders should be properly discovered this way. Eclipse might want to install some additional integrations for Maven features that this particular project uses. Let it, if that is the case.

Now, you will have the project operational and compiling in Eclipse, but it will not be aware that it is managed by Git... This is because M2Eclipse and Git Team provider are not integrated (at least they weren't when I last checked). In order to be able to commit to the repository in Eclipse, remove the project from workspace, but without deleting contents. Then, import from Repository view using Import Projects/Import exsisting Eclipse projects. Since necessary .project file is already generated, Eclipse will autodiscover the project and will use the right configuration prepared earlier by M2Eclipse.

In the end you will have a properly configured Maven project with Git as a team provider for it.