Victoria's Blog

m2eclipse plugin error message

I’ve been installing Eclipse with all of the plugins I usually use nowadays (m2eclipse, checkstyle, etc.) but had encountered a problem after installing m2eclipse. The error was as follows:

Could not calculate build plan: Missing:
----------
1) org.apache.maven.plugins:maven-resources-plugin:maven-plugin:2.4.1
Try downloading the file manually from the project website.
Then, install it using the command: 
mvn install:install-file -DgroupId=org.apache.maven.plugins -DartifactId=maven-resources-plugin -Dversion=2.4.1 -Dpackaging=maven-plugin -Dfile=/path/to/file
Alternatively, if you host your own repository you can deploy the file there: 
mvn deploy:deploy-file -DgroupId=org.apache.maven.plugins -DartifactId=maven-resources-plugin -Dversion=2.4.1 -Dpackaging=maven-plugin -Dfile=/path/to/file -Durl=[url] -DrepositoryId=[id]
----------
1 required artifact is missing.
for artifact: 
org.apache.maven.plugins:maven-resources-plugin:maven-plugin:2.4.1
from the specified remote repositories:
central (http://repo1.maven.org/maven2, releases=true, snapshots=false)

Rather non-descript error there. Had a quick google around and there are a few people posting similar error messages but none of the pages had an answer on how to fix it. I checked the .m2eclipse file to make sure it was correct, which it seems to be. And then I had a bit of a brain wave! (Unusual yes). Every post I’d seen had mentioned that the plugin was definitely in the repository, but Eclipse was claiming it couldn’t find it. So I checked ZoneAlarm and deleted all entries that didn’t have Access-trusted and internet. Lo and behold, Java™ Platform SE binary pops up a dialog box straight away and when I allowed it access, Eclipse began to download successfully from the repository!

But the error is still there… So attempt 2, add the plugin to the plugins tab, but move the plugin to the next version 2.4.2.

<plugins>
  	<plugin>
 		<groupId>org.apache.maven.plugins</groupId>
		<artifactId>maven-resources-plugin</artifactId>
		<version>2.4.2</version>
	</plugin>
</plugins>

The error is now gone, but not sure this is the best solution, so if anyone can think of a better one, let me know!

Anyway hope this helps someone else with this error message.