Why can't add child to the node created by appendNode()?

Question

I want to create a xml like this:

<root>
  <level1>
    <levl2/>
  </level1>
</root>

Here is my groovy code:

def root="<root/>"
def l1 = "<level1/>"
def l2 = "<level2/>"

def dom = new XmlSlurper(false, false).parseText(root)
dom.appendNode(new XmlSlurper().parseText(l1))
dom.level1.appendNode(new XmlSlurper().parseText(l2))
def sw = new StringWriter()
XmlUtil.serialize(dom, sw)
println sw.toString()

The actual result of my code is like this:

<root>
  <level1/>
</root>

Could anyone tell me what's wrong?

Answer 1

Because appendNode() always appends at the end of the document, so you do not need to specify the last node. In your example, since l2 has to be added as a child to l1 so using leftShift will be an easier option:

def root="<root/>"
def l1 = "<level1/>"
def l2 = "<level2/>"

def dom = new XmlSlurper(false, false).parseText(root)

dom << ( new XmlSlurper().parseText( l1 ) << new XmlSlurper().parseText( l2 ) )

def sw = new StringWriter()
XmlUtil.serialize(dom, sw)
println sw.toString()

Is there any reason you cannot use like this:

dom.root {
    level1 {
        level2 { }
    }
}

Normally, it is done using MarkupBuilder as:

def swr = new StringWriter()
def markup = new groovy.xml.MarkupBuilder(swr)
markup.root {
    level1 {
        level2 { }
    }
}


println swr

What is the intention here using appendNode?