groovy.lang.GroovyRuntimeException: Failed to create Script instance for class: class WorkflowScript. Reason: java.lang.NullPointerException
	at org.codehaus.groovy.runtime.InvokerHelper.createScript(InvokerHelper.java:464)
	at groovy.lang.GroovyShell.parse(GroovyShell.java:700)
	at org.jenkinsci.plugins.workflow.cps.CpsGroovyShell.reparse(CpsGroovyShell.java:67)
	at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.parseScript(CpsFlowExecution.java:411)
	at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.start(CpsFlowExecution.java:374)
	at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:220)
	at hudson.model.ResourceController.execute(ResourceController.java:98)
	at hudson.model.Executor.run(Executor.java:404)
Caused by: java.lang.NullPointerException
	at org.jenkinsci.plugins.workflow.cps.CpsScript.$build(CpsScript.java:141)
	at org.jenkinsci.plugins.workflow.cps.EnvActionImpl$Binder.getValue(EnvActionImpl.java:140)
	at org.jenkinsci.plugins.workflow.cps.EnvActionImpl$Binder.getValue(EnvActionImpl.java:135)
	at org.jenkinsci.plugins.workflow.cps.CpsScript.getProperty(CpsScript.java:121)
	at org.codehaus.groovy.runtime.callsite.PogoGetPropertySite.getProperty(PogoGetPropertySite.java:50)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGroovyObjectGetProperty(AbstractCallSite.java:307)
	at WorkflowScript.<init>(WorkflowScript)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	at java.lang.reflect.Constructor.newInstance(Unknown Source)
	at java.lang.Class.newInstance(Unknown Source)
	at org.codehaus.groovy.runtime.InvokerHelper.createScript(InvokerHelper.java:432)
	... 7 more