[ERROR] Failed to execute goal de.monticore.lang.monticar.utilities:maven-streamtest:0.0.26-SNAPSHOT:streamtest-build (default-cli) on project mnist-calculator: Execution default-cli of goal de.monticore.lang.monticar.utilities:maven-streamtest:0.0.26-SNAPSHOT:streamtest-build failed.: NullPointerException -> [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/PluginExecutionException Cleaning up project directory and file based variables ERROR: Job failed: exit code 1