Is it possible to view a multi-module Maven project in Eclipse as a hierarchy?
I solved this problem as follows:
Under the "Project Explorer" click on the "View Menu" (little triangle) and select "Filters and Customization..."
Under the "Content" tab tick "Nested Projects"
Finally, Under the "Pre-set filters" tab tick "Nested Projects: hide folders when projects is shown as nested" and "Nested Projects: hide-top-level project if shown as nested".
By doing that I come up with the following structure.
Since Eclipse 4.5 it is possible to see a multi-module maven project as a tree. In order to do that you need to import all modules as separate projects, then on "Project Explorer" view click "View Menu" (the triangle button), choose "Customize view" and on "Content" tab tick "Nested Projects". This tree representation doesn't work in "Package Explorer" view, only in "Project Explorer".