Building error

[moritomo]

I tried to build by "mvn clean package". But I got following error messages.

[ERROR] Failed to execute goal on project to-utf8-action-plugin: Could not resolve dependencies for project io.cdap.plugin:to-utf8-action-plugin:jar:1.1.0: The following artifacts could not be resolved: io.cdap.cdap:cdap-api:jar:6.0.0-SNAPSHOT, io.cdap.cdap:cdap-etl-api:jar:6.0.0-SNAPSHOT, io.cdap.cdap:hydrator-test:jar:6.0.0-SNAPSHOT, jdk.tools:jdk.tools:jar:1.6: Failure to find io.cdap.cdap:cdap-api:jar:6.0.0-SNAPSHOT in https://oss.sonatype.org/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of sonatype has elapsed or updates are forced -> [Help 1]

This issue looks the same error.
If so, does anyone update in the same way?