Groovy script fails to resolve class com.cloudbees.hudson.plugins.modeling.Model

Issue

Previously working groovy scripts started to fail after upgrading your Jenkins instance

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
Script1.groovy: 1: unable to resolve class com.cloudbees.hudson.plugins.modeling.Model

Environment

CloudBees CI (CloudBees Core) on modern cloud platforms - Managed controller
CloudBees CI (CloudBees Core) on modern cloud platforms - Operations Center
CloudBees CI (CloudBees Core) on traditional platforms - Client controller
CloudBees CI (CloudBees Core) on traditional platforms - Operations Center
CloudBees Jenkins Enterprise - Managed controller

Description

You may notice that a simple groovy script that was successfully running on Jenkins instances including version 2.138.4.3-rolling

import com.cloudbees.hudson.plugins.modeling.Model
print "Done"

started to fail when you upgraded to Jenkins version 2.164.1.2-rolling or later. The exact error reads

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
Script1.groovy: 1: unable to resolve class com.cloudbees.hudson.plugins.modeling.Model
 @ line 1, column 1.
   import com.cloudbees.hudson.plugins.modeling.Model
   ^

1 error

	at org.codehaus.groovy.control.ErrorCollector.failIfErrors(ErrorCollector.java:310)
	at org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:958)
	at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:605)
	at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:554)
	at groovy.lang.GroovyClassLoader.doParseClass(GroovyClassLoader.java:298)
	at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:268)
	at groovy.lang.GroovyShell.parseClass(GroovyShell.java:688)
	at groovy.lang.GroovyShell.parse(GroovyShell.java:700)

Resolution

Using a wildcard with Java import statement resolves the error

import com.cloudbees.hudson.plugins.modeling.*

This article is part of our Knowledge Base and is provided for guidance-based purposes only. The solutions or workarounds described here are not officially supported by CloudBees and may not be applicable in all environments. Use at your own discretion, and test changes in a safe environment before applying them to production systems.