Remove empty tags from XML in Groovy

Question

Sorry for bothering with a primitive question. i have a the following xml output with the multi map format.

The empty tags and the multi map tags need to be removed from the xml.

<?xml version='1.0' encoding='UTF-8'?>
<multimap:Messages xmlns:multimap="http://sap.com/xi/XI/SplitAndMerge">
    <multimap:Message1>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets>
                <id>1234</id>
                <field2>4496</field2>
                <field3>test</field3>
            </budgets>
        </root>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets>
        </root>
    </multimap:Message1>
</multimap:Messages>

The expected output as follows

<base1> 
    <root>
        <budgets>
            <id>1234</id>
            <field2>4496</field2>
            <field3>test</field3>
        </budgets>
    </root>
</base1>

tried the following code,

def body = message.getBody(java.lang.String) as String;
body = body.replaceAll("<multimap:Messages xmlns:multimap=", "");
body = body.replaceAll("\"http://sap.com/xi/XI/SplitAndMerge\">", "");
body = body.replaceAll("</multimap:Messages>", "");
body = body.replaceAll("multimap:Message", "base")
body = body.replaceAll("\\<\\?xml(.+?)\\?\\>", "").trim();

def list = new XmlParser().parseText(body)
def list1 = list.'**'.findAll{it.children().size() == 0 }
list1.each{ 
    list.remove(it)
}

Tried with the following code as well:

list.'**'.removeAll{ it.children().size() == 0 }

Not sure what i am missing here. Your help in solving this is highly appreciated.

Answer 1

Using some simple XML processing:

import groovy.xml.*

def xml = new XmlSlurper().parseText '''\
<?xml version='1.0' encoding='UTF-8'?>
<multimap:Messages xmlns:multimap="http://sap.com/xi/XI/SplitAndMerge">
    <multimap:Message1>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets>
                <id>1234</id>
                <field2>4496</field2>
                <field3>test</field3>
            </budgets>
        </root>
        <root>
            <budgets/>
        </root>
        <root>
            <budgets/>
        </root>
    </multimap:Message1>
</multimap:Messages>'''

List notEmptyBudgets = xml.'**'.findAll{ 'budgets' == it.name() && it.children().size() }

def writer = new StringWriter()

def out = new StreamingMarkupBuilder().bind{
  base1{
    root{
      notEmptyBudgets.each{ b ->
        budgets{
          b.children().each{ "${it.name()}" it.text() }
        }
      }
    }
  }
}

XmlUtil.serialize out

returns

<?xml version="1.0" encoding="UTF-8"?><base1>
  <root>
    <budgets>
      <id>1234</id>
      <field2>4496</field2>
      <field3>test</field3>
    </budgets>
  </root>
</base1>