An external java library is treated as "package only containing non Java resources" (as indicated by the white icons as opposed to brown; the description in quotes is taken from here). When I try to import the library it cannot be resolved, so it seems it really isn't being recognised (in other words it's not just a case of eclipse showing wrong icon).
Two people have commented that my screenshots are not helping, so let me explain the intention behind them. The first one above is to show the difference between how my libraries are displayed. Htmlparser is a folder with .java files just like SPMF and works fine. Commons-lang and vecmath are .jars. SPMF cannot be resolved when I try to import it. The reason the screenshot is cropped this way is to highlight that all of the folders in SPMF are showing white which apparently means they are not recognized.
This is only the second time I'm using an external library, but I think I did everything the same as the first time.
This screenshot is intended to show how SPMF is added at the moment.
The library I am trying to add is SPMF - more specifically the Hierarchical Clustering algorithm. This is only a minor component of SPMF but it's the best Hierarchical Clustering solution I could find. It works fine if I just import it into a new project. So I could just bodge it by moving my code into that project if I can't get it going otherwise.
I presume that if a package can form a standalone project then it can also be used as an external library - or am I wrong?
I'm sure it's a stupid mistake I'm making but I've had no luck with google. This is the nearest I could find; Refresh seems the only applicable solution and it doesn't help.
Edit, SPMF is also available as a jar, it's missing some features but not the ones I need. I've been able to add the jar and the import the algorithm I need. It's enough of a workaround for me to move on and keep going. But it's not a solution and the question remains open.
