passing testsuite properties for REST headers?

Hi all,

I am trying to pass a test suite property to fill a REST header using groovy scripts. I tried the below, but could not succeed. I am getting error "java.lang.ClassCastException: org.codehaus.groovy.runtime.GStringImpl cannot be cast to java.lang.string".

Can anyone help me to overcome this?

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import com.eviware.soapui.support.types.StringToStringMap

def headers = new StringToStringMap()
def user1 = testRunner.testCase.testSuite.getPropertyValue( "usera" )
//just to check whether it fills correctly
log.info("$user1")
headers.put("authorization","$user1")
headers.put("Content-Type","application/json")
testRunner.testCase.getTestStepByName("Profile - Get Profile").testRequest.setRequestHeaders(headers)

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Thanks & Regards,
Rajesh