I guess this is a Eclipse question.
I have a mercurial repository with a source folder (src/main/java/) and some source code. The repository also contains a build.xml. After cloning the project into Eclipse using the Mercurial plugin I'm unable to configure a launch configuration for my project. Eclipse is unable to identify the newly cloned project as a project when setting up the launch configuration. What am I missing?
TIA
What kind of launch configuration are you using?
an External Tools Configuration (in which case you defnie and Ant Build with a direct link to your build.xml)
or a "Run Configuration", meaning your repository must include a .eclipse and a .classpath for eclipse to list your project as one being able to Run.
As discussed before in Which eclipse files belong under Version Control, those two files can be versioned, provided they only use relative path.
Do you have a .project file?
If you do, you should be able to use File->Import->General->Existing Projects into Workspace.
If you don't, try File->New->Project and there are various different options to create a project from existing source.