How to fetch Cobertura LineCoverage in groovy

[Prasanth Thampi]

My groovy script is failing due to null pointer error. 

can any one help me in understanding what to be fixed

~~~

build.getAction(hudson.plugins.cobertura.CoberturaBuildAction.class).getLineCoverage().getPercentageFloat();

~~~

Groovy script failed:

java.lang.NullPointerException: Cannot invoke method getLineCoverage() on null object
	at org.codehaus.groovy.runtime.NullObject.invokeMethod(NullObject.java:77)
	at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.call(PogoMetaClassSite.java:45)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
	at org.codehaus.groovy.runtime.callsite.NullCallSite.call(NullCallSite.java:32)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:112)
	at Script1.coverage(Script1.groovy:5)
	at Script1$coverage.callCurrent(Unknown Source)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:46)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:133)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:141)
	at Script1.run(Script1.groovy:19)
	at groovy.lang.GroovyShell.evaluate(GroovyShell.java:580)
	at groovy.lang.GroovyShell.evaluate(GroovyShell.java:618)
	at groovy.lang.GroovyShell.evaluate(GroovyShell.java:589)
	at org.jenkinsci.plugins.scriptsecurity.sandbox.groovy.SecureGroovyScript.evaluate(SecureGroovyScript.java:166)
	at org.jvnet.hudson.plugins.groovypostbuild.GroovyPostbuildRecorder.perform(GroovyPostbuildRecorder.java:361)
	at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
	at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:770)
	at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:734)
	at hudson.model.Build$BuildExecution.post2(Build.java:183)
	at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:683)
	at hudson.model.Run.execute(Run.java:1784)
	at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
	at hudson.model.ResourceController.execute(ResourceController.java:89)
	at hudson.model.Executor.run(Executor.java:240)

[Surya Gaddipati]

What you are doing seems right. 

Looks like the build in question did not run cobertura .