[ERROR] Plugin org.apache.maven.plugins:maven-shade-plugin:2.4.1 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-shade-plugin:jar:2.4.1: 4 problems were encountered while building the effective model for :maven-shade-plugin:2.4.1
[ERROR] [ERROR] Invalid packaging for parent POM [unknown-group-id]:[unknown-artifact-id]:[unknown-version], must be "pom" but is "jar" @ [unknown-group-id]:[unknown-artifact-id]:[unknown-version]
[ERROR] [ERROR] 'groupId' is missing. @ org.apache.maven.plugins:maven-shade-plugin:2.4.1
[ERROR] [ERROR] 'dependencies.dependency.version' for org.apache.maven.plugin-tools:maven-plugin-annotations:jar is missing. @ org.apache.maven.plugins:maven-shade-plugin:2.4.1
[ERROR] [ERROR] 'dependencies.dependency.version' for org.codehaus.plexus:plexus-component-annotations:jar is missing. @ org.apache.maven.plugins:maven-shade-plugin:2.4.1
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginResolutionException
请各位大神，帮小弟看看 这是什么问题
