Using xpath returns arraylist instead of nodelist

Attaching code that would demonstrate this problem would probably expidite it's getting fixed...

for example....

class quickController {
   def index = {
        def xml = '<root><Items><Item>...</Item><Item>...</Item></Items></root>'
        def doc = ??? slurper ???
        for(item in doc.Items.item){
             // assert item.class == NodeList
             // I'm suprised that this is now an ArrayList
             assert item.class == ArrayList
        }
   }
}

This is working code.

def testgroovy1 = {
def xmlData = "<root><Items><Item>data1</Item><Item>data2</Item></Items></root>"
def doc = new XmlParser().parseText(xmlData)
def items = doc.Items.Item
// I'm suprised that "items" is now an ArrayList. It used to be a NodeList. Isn't this a bug?
assert items.class == ArrayList
for (item in items)

}

I tried on 1.6.7 / 1.6.8/1.7.1 snapshots and I don't see this issue.

I see groovy.util.NodeList / groovy.util.Node classes and not ArrayList

def xmlData = "<root><Items><Item>data1</Item><Item>data2</Item></Items></root>"
def doc = new XmlParser().parseText(xmlData)
def items = doc.Items.Item

println items.getClass() // is groovy.util.NodeList

for (item in items)
{ 
	// now instead of item being one of the actual item nodes it is a nodelist 
	// of the actual nodes. 
	println item.getClass() // is groovy.util.Node
}

Can you check the groovy version being used using GroovySystem.version?

Could you be a bit more precise in your descriptiong of the problem?
Could you show us some more code, so we understand exactly what's going on?

This was on the version of Groovy 1.6.3 that came with Grails 1.2. So perhaps it has been fixed?

We are in the process of upgrading from Grails 1.1.1 to 1.2 and are experiencing the same problem.

The application processes this XML

<Page number="1" width="612" height="792">
<Content granularity="word" font="true" geometry="true">
<Para>
<Word>
<Text>CLARKSVILLE</Text>
<Box llx="45.00" lly="704.52" urx="139.69" ury="718.08">
...

using this code

def insertLineElements(pageXml)
{
pageXml.Content.Para.each()

(The program still does not work because there are many other places in the code with a similar problem - the parser went completely wild).

It appears this problem is specific to Grails. We tried to replicate it by writing a similar Groovy program (using 1.6.7 version of Groovy used by Grails 1.2) and could not replicate it.

Michael

Hello Michael,

Here's a little helper file I wrote. I wrap getNodeList around every call that has the problem.

class XmlHelper {


  // Use this when using xpath to get around bug in grails 1.2
  static def getNodeList (nodelist)
  {
    if (nodelist.class == ArrayList)
    {
      return nodelist[0]
    }
    else
    {
      return nodelist
    }
  }


  static def getNodeName (node)
  {
    def n = node.name()
    if (n instanceof groovy.xml.QName)
    {
      return n.getLocalPart()
    }
    else
    {
      return n.toString()
    }
  }

}

Andrew, thank you for your help. Changing the code to make it work correctly was not the a big problem. XmlParser gives you dozens of ways of accomplishing the same goal, so I managed to rewrite the code that it works.

What concern me was that the upgrade to Grails 1.2 required me to make all those changes. I would like to understand why XmlParser is behaving differently in Grails 1.2 than it did in 1.1.1 from which I upgraded. Was my code incorrect and XmlParser is stricter about following certain conventions or was a bug introduced into the ecosystem?

The issue I have mentioned was not the only one that required me to change the code. For example, where before I could write

box.@llx

had to be rewritten as

box.'@llx'

Were there changes in Groovy language that would cause such change in XmlParser behavior?

Michael

This is a very strange issue

I use XmlParser to update an XML file used within IzPack.
basically, I have to update the src attribute of the following node,
<res id="jlinkProe" src="./installer/shared_lib/xxxxx"/>

I used the following code :

The following examples can be tested in the grails console

xtext = """<?xml version="1.0" encoding="iso-8859-1" standalone="yes" ?>
<!-- <!DOCTYPE installation SYSTEM "./installation.dtd"> -->

<installation version="1.0">


    <resources>
        
        <res id="LicencePanel.licence" src="./installer/resources/Licence.txt"/>
        <res id="InfoPanel.info" src="./installer/resources/Readme.txt"/>
        <res id="ProcessPanel.Spec.xml" src="./installer/scripts/ProcessPanel.Spec.xml"/>
        <res id="userInputSpec.xml" src="./installer/scripts/userInputSpec.xml"/>
        <res id="pworker.war" src="./installer/staging/pworker.war"/>
        <res id="DSL" src="./installer/staging/DSL.zip"/>


        <res id="jlinkWraper" src="./installer/shared_lib/jlinkWrapper.jar"/>
        <res id="jlinkProe" src="./installer/shared_lib/xxxxx"/>
    </resources>

</installation>"""



   installation = (new XmlParser()).parseText(xtext)
   println "gne ? : ${installation.resources.res.class}"
   proeNode = installation.resources.res.find({
   println "cherchenode ${it.'@id'}"
   println it.class
    it.'@id' == 'jlinkProe'
     })
     
  proeNode.'@src' = "./installer/shared_lib/tatayoyo"
   
  
   proeNode
   

I made the following modifications to make it work.

proeNode = installation.resources.res [0].find({

proeNode. attributes['src'] = "./installer/shared_lib/tatayoyo"

This is definitely a grails issue, as I can't reproduce it in pure groovy code.

xtext = """<?xml version="1.0" encoding="iso-8859-1" standalone="yes" ?>
<!-- <!DOCTYPE installation SYSTEM "./installation.dtd"> -->

<installation version="1.0">


    <resources>
        
        <res id="LicencePanel.licence" src="./installer/resources/Licence.txt"/>
        <res id="InfoPanel.info" src="./installer/resources/Readme.txt"/>
        <res id="ProcessPanel.Spec.xml" src="./installer/scripts/ProcessPanel.Spec.xml"/>
        <res id="userInputSpec.xml" src="./installer/scripts/userInputSpec.xml"/>
        <res id="pworker.war" src="./installer/staging/pworker.war"/>
        <res id="DSL" src="./installer/staging/DSL.zip"/>


        <res id="jlinkWraper" src="./installer/shared_lib/jlinkWrapper.jar"/>
        <res id="jlinkProe" src="./installer/shared_lib/xxxxx"/>
    </resources>

</installation>"""



   installation = (new XmlParser()).parseText(xtext)
   println "class  : ${installation.resources.res.class}"
   proeNode = installation.resources.res[0].find({
   println "cherchenode ${it.'@id'}"
   println it.class
    it.'@id' == 'jlinkProe'
     })
     
  proeNode.attributes['src'] = "./installer/shared_lib/tatayoyo"
   
  
   proeNode
   

There doesn't seem to be a consensus as to whether this is a groovy or grails issue. In fact, it seems like we don't have a standalone groovy failing test case. I am thinking of closing the issue and we can re-open or create a new one if we can find an example of the problem again. Any objections?

No objections raised to closing. Please open a new issue with a standalone Groovy test case if you are still having problems.