Can't use Maven on Eclipse

Question

I installed a new Eclipse EE 4.9 and downloaded the newest Maven. In Windwows->Preferences->Maven:

->Installations: I chose the freshly downloaded Maven

->User Settings: I chose [PATH-TO-MAVEN]\conf\settings.xml

When I try to create a simple Maven project, I get that error:

Could not calculate build plan: Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6 Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6

Also, when I open the pom.xml of that project, it says on the line with <packaging>:

<project [...]>
[...]
  <packaging>war</packaging> // <-- here seems to be an error
</project>

that there seems to be an error:

Multiple annotations found at this line:

CoreException: Could not calculate build plan: Plugin org.apache.maven.plugins:maven-compiler-plugin:3.1 or one of its dependencies could not be resolved: Failed to read artifact
descriptor for org.apache.maven.plugins:maven-compiler-plugin:jar:3.1: ArtifactResolutionException: Failure to transfer org.apache.maven.plugins:maven-compiler-plugin:pom:3.1 from https://
repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced. Original error: Could not transfer artifact org.apache.maven.plugins:maven-compiler-plugin:pom:3.1 from/to central (https://repo.maven.apache.org/maven2): sun.security.validator.ValidatorException: PKIX path building
failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

Plugin execution not covered by lifecycle configuration: org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile (execution: default-testCompile, phase: test-compile)

Does anybody have an idea?

@Sir.Hedgehog: m2e is installed in Eclipse EE per default. I assume, otherwise there wouldn't be the option to create a Maven project. — Evgenij Reznik
nope, same thing happened to me last week. IDE had it installed, but you need to provide the directory that the maven exists. look into it, that might be it. — Sir. Hedgehog

mkane mkane · Accepted Answer · 2018-10-15T13:42:21

Looks like there is an issue going over https to the repo.

i.e. sun.security.validator.ValidatorException: PKIX path building

Check the version of Java you are using an ensure that you are not passing an incorrect path to the trust store..

i.e.

-Djavax.net.ssl.trustStore

Have a look at https://confluence.atlassian.com/kb/unable-to-connect-to-ssl-services-due-to-pkix-path-building-failed-779355358.html as there are other resolutions at the bottom of the article..

Just also noted that an issue similar to this has been discussed and anserwed in great detail @ Problems using Maven and SSL behind proxy..

Can't use Maven on Eclipse

1 Answers