Diff XML files in SoapUI with Groovy, ignoring GUID and timestamp differences

gistfile1.groovy

// In each testcase script assertion:
//
import FileCompare
FileCompare.compareWithExpected(context, messageExchange)


// In our Script Library:
//
package filecompare
class FileCompare {
  def static compareWithExpected(context, mex) {
    def testCase = context.testCase.name.toLowerCase()
    def testSuite = context.testCase.testSuite.name
    def projectDir = new File(context.testCase.testSuite.project.path).parent
    def expectedFilename = "$projectDir/expected_responses/${testSuite}/${testCase}"
    def gotFilename = "${expectedFilename}_got.xml"
    new File(gotFilename).write(mex.responseContentAsXml)

    def ignoreGUIDs = "-I \"[0-9a-f]\\{32\\}\""
    def ignoreDates = "-I \"[0-9]*\\/[0-9]*\\/[0-9]\\{4\\}\""
    def diffCmd = "diff -bq --strip-trailing-cr $ignoreGUIDs $ignoreDates ${expectedFilename}.xml $gotFilename"
    def results = diffCmd.execute()
    results.waitFor()

    assert results.exitValue() == 0
    results.destroy()
  }
}

Hi,

Recently started using groovy for soapui automation . As part of this, i need to compare expected xml file with soap response xml. Some of the node values in xml are dynamic.

Error message

Getting an error at "def results = diffCmd.execute()".
Do i need to import any package to resolve the issue ? and how to print xml difference value to console?