希望这就是你想要的。

import groovy.xml.MarkupBuilder
import groovy.xml.XmlSlurper
import groovy.xml.XmlUtil

def startingXmlTxt =
'''<root>
    <FirstName>John</FirstName>
    <LastName>Major</LastName>
</root>'''

def startingXml = new XmlSlurper().parseText(startingXmlTxt)

def sw = new StringWriter()
def bldr = new MarkupBuilder(sw)

bldr.root {
    startingXml.'*'.each { aRt ->
        row {
            Key(aRt.name())
            Value(aRt.text())
        }
    }
}

println XmlUtil.serialize( new XmlSlurper().parseText( sw.toString() ) )

然后回来...

startingXml = new XmlSlurper().parseText(sw.toString())
sw = new StringWriter()
bldr = new MarkupBuilder(sw)

bldr.root {
    startingXml.'*'.each{ aRt ->
        "${aRt.Key}"( aRt.Value )
    }
}

println XmlUtil.serialize( new XmlSlurper().parseText( sw.toString() ) )