Cannot Invoke method getRowCount

Hi – Please can you help?

I am doing the below as indicated in your video datadrivenframework SOAP UI free version.

1. I created a groovy step – “init” with the below code.

import com.soapuitutorial.property.*

if(context.xls == null){

context.xls = new Xls_Reader("C:\\Users\\Copy of Tests.xlsx")

context.rowNum=2

}

context.polid = context.xls.getCellData("polstat", "polid", context.rowNum)

log.info "Data from XLS--> " + context.polid

2) Created another groovy step called “loop”

if(context.rowNum < context.xls.getRowCount("polstat ")){

                context.rowNum++

                testRunner.gottoStepByName("init")

}

When I run them together I get the below error in the loop step

Java.lang.NullPointerException“Cannot Invoke method getRowCount() on null object”

Please let me know where I went wrong.