dummy:dummy:jar:1.0, surefire-junit4, maven and Nexus
So we recently implemented a Nexus server for our maven repository manager. We proxy about 30 outside repositories and funnel them all into a single group, which we point to in the settings.xml in mirrors with a *.
Before that, we didn't have this problem... and now we do. It frustrates me that there is little information on this dummy jar, where it comes from, or where I can get it to stop these failures. I have been researching for a few days and come up short with nothing. I am hoping the community might be able to help.
18-Oct-2012 22:50:31 [ERROR] BUILD ERROR
18-Oct-2012 22:50:31 [INFO] ------------------------------------------------------------------------
18-Oct-2012 22:50:31 [INFO] Unable to generate classpath: org.apache.maven.artifact.resolver.ArtifactResolutionException: Unable to get dependency information: Unable to read the metadata file for artifact 'org.apache.maven.surefire:surefire-junit4:jar': Cannot find parent: org.apache.maven.surefire:surefire-providers for project: null:surefire-junit4:jar:null for project null:surefire-junit4:jar:null
18-Oct-2012 22:50:31 org.apache.maven.surefire:surefire-junit4:jar:2.12
18-Oct-2012 22:50:31
18-Oct-2012 22:50:31 from the specified remote repositories:
18-Oct-2012 22:50:31 central (http://repo1.maven.org/maven2),
18-Oct-2012 22:50:31 JavaNet-mirror (http://maven:8081/nexus/content/repositories/Java.net/),
18-Oct-2012 22:50:31 Releases (https://nexus:8443/nexus/content/repositories/releases/)
18-Oct-2012 22:50:31
18-Oct-2012 22:50:31 Path to dependency:
18-Oct-2012 22:50:31 1) dummy:dummy:jar:1.0
Answer
We had a similar problem where a developer had put a class with the name of "TestUtil" in the test hierarchy, when the class wasn't actually related to unit testing at all. Renaming the class into something that didn't contain Test prefix fixed the issue for us. Don't know what it is about though.
AFAIK dummy.jar is something used internally by surefire plugin but is normally never exposed to end user. "dummy.jar" can be seen in surefire plugin source code (example1 and example2)
So in our case the class "TestUtil" caused the problem to appear, leading to similar situation, but to verify it's not something more logical always do a run of maven with -X debug log flag set.