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We're using Maven at work at quite regularly we get the error message "The artifact has no valid ranges". After a long time of Googling and experimenting I realised what this error message means: The artifact does have valid ranges, just too many of them.

For example, my master POM has a dependency on superframework v.1.0 only, but there is also a transitive dependency on superframework v.0.5-0.9.

Until now, whenever I had such a problem I've looked at the (very cryptic) error message and sorta guessed which POM I needed to change - basically a lot of trial an error. The problem is that mvn dependency:tree doesn't work if you have a dependency resolution problem.

The Eclipse plugin sometimes helps a little, but sometimes it is way off.

Any tips on how to resolve these problems?

Pascal Thivent
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Leonard Ehrenfried
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2 Answers2

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This might not be the expected answer but my advice would be to actually not use dependency ranges as they worsen build reproducibility.

I prefer to use fixed versions (which also make dependencies conflicts resolution easier, see the note at the bottom of 9.4.3. Dependency Version Ranges) and use intensively the Dependency Convergence report to manage them.

Pascal Thivent
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  • Thanks for this answer; I will try to get the word out at work. – Leonard Ehrenfried Nov 04 '09 at 11:15
  • The link in the answer seems not to work anymore, the new one is: http://www.sonatype.com/books/mvnref-book/reference/pom-relationships-sect-project-dependencies.html#pom-relationships-sect-version-ranges – Jiri Patera Aug 29 '12 at 08:25
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This isn't a direct answer to my question but rather a word of advice. I learned something new since askin the question: the order in which dependencies are listed in the POM files, much to my surprise, does matter.

So, if you include a dependency on 

superframework [0.5,1.5)

it will fetch the latest available version, say 1.1.

If you then have a transitive dependency further down that includes 

superframework [0.5, 1.0)

Maven will generate this misleading error, since it will not select anything other than the 1.1 it already has, even though it could just select 0.9 without producing a version conflict. If you swap the order, weirdly, it works.

Am I right in thinking that this is a flaw in Maven's behaviour?

Leonard Ehrenfried
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  • This might be related to the way Maven resolves dependencies (and conflicts), see http://docs.codehaus.org/display/MAVEN/Dependency+Mediation+and+Conflict+Resolution. Another good reason to not use ranges IMHO. – Pascal Thivent Nov 04 '09 at 16:34