[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of itsdependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6: Could not transfer

artifactorg.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (https://repo.maven.apache.org/maven2): repo.maven.apache.org: Unknown host repo.maven.

apache.org -> 

出现了这个错，怎么解决？