XML Parsing using groovy

Question

How can I parse following XML file using Groovy

<Person>
    <name>a</name>
    <age>1</age>
</person>
<account>
    <number>4242</number>
    <bank>S</bank>
</account>
<account>
    <number>4242</number>
    <bank>T</bank>
</account>
<Person>
    <name>b</name>
    <age>1</age>
</person>
<account>
    <number>4242</number>
    <bank>S</bank>
</account>
<account>
    <number>4242</number>
    <bank>T</bank>
</account>

In this case person can have multiple accounts.How can I parse this xml?

Person A - finding all of bank accounts using groovy

Answer 1

This is pretty ugly, but if there is no way to change the XML being received, you can iterate it using old school index manipulation.

The XML and some fixing:

def xml = '''
<Person>
    <name>a</name>
    <age>1</age>
</person>
<account>
    <number>4242</number>
    <bank>S</bank>
</account>
<account>
    <number>4242</number>
    <bank>T</bank>
</account>
<Person>
    <name>b</name>
    <age>1</age>
</person>
<account>
    <number>4242</number>
    <bank>S</bank>
</account>
<account>
    <number>4242</number>
    <bank>T</bank>
</account>'''

fixedXml = "<root>${xml.replaceAll('<Person>', '<person>')}</root>"

And the processing:

def root = new XmlParser().parseText fixedXml

def people = [:]

for (int i = 0; i < root.children().size(); i++) {
  def child = root.children()[i]

  if (child.name() == 'person') {

    people[child] = []

    while(true) {
      def nextChild = root.children()[i + 1]
      if (nextChild?.name() == 'account') {
        people[child] << nextChild
        i++
      } else {
        break
      }
    }

  }
}

assert people.size() == 2
assert people*.value*.size == [2, 2]
assert people['a'][0].bank.text() == "S"
assert people['b'][1].number.text() == "4242"

If the XML is worst than that, consider using neko to clean it.

Answer 2

Mark is right, first you need a well formated xml document. Then, you can use XmlSlurper (or XmlParser), both return an implementation of GPath.

Here I've added <root> and <accounts> tags to make the document xml valid:

 def doc = """
    <root>
        <person>
            <name>a</name>
            <age>1</age>
            <accounts>
                <account>
                    <number>4242</number>
                    <bank>S</bank>
                </account>
                <account>
                    <number>5252</number>
                    <bank>T</bank>
                </account>
            </accounts>
        </person>
        <person>    
            <name>b</name>
            <age>1</age>
            <accounts>
                <account>
                    <number>4242</number>
                    <bank>S</bank>
                </account>
                <account>
                    <number>4242</number>
                    <bank>T</bank>        
                </account>
            </accounts>
        </person>
    </root>
    """

then it's pretty easy to parse it with GPath:

def parser = new XmlSlurper().parseText(doc)
parser.person.findAll { p -> p.name == 'a' }
    .accounts.account.number.each {  v -> println "Account number[$v]" }

which renders:

Account number[4242]

Account number[5252]