1

I am actually working on windows and I have to parse xml from a file.

The issue is when i parse the root element, and get the children via the child method, I am getting empty children.

XML.load("my_path\\sof.xml").child

res0: Seq[scala.xml.Node] = List(
    , <b/>, 
)

This is my xml file

sof.xml
<a>
    <b></b>
</a>

But when I remove every \n and \r of the file like this :

sof.xml
<a><b></b></a>

I got the following result which is expected 

res0: Seq[scala.xml.Node] = List(<b/>)

My question is, is there an option to read it correctly from the intended form?

BlueSheepToken
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2 Answers2

2

The issue is the newlines/whitespace are treated as Text nodes. The scala.xml.Utility.trim(x: Node) method will remove the unnecessary whitespace:

scala> val a = XML.loadString("""<a>
     |     <b></b>
     | </a>""")
a: scala.xml.Elem =
<a>
    <b/>
</a>

scala> scala.xml.Utility.trim(a)
res0: scala.xml.Node = <a><b/></a>

Note that this differs from the .collect method if you have actual Text nodes inbetween elements, e.g.:

scala> val a = XML.loadString("""<a>
     |    <b>Test </b>   Foo    
     |    </a>""")
a: scala.xml.Elem =
<a>
   <b>Test </b>   Foo
</a>

scala> scala.xml.Utility.trim(a).child
res0: Seq[scala.xml.Node] = List(<b>Test</b>, Test)

scala> a.child.collect { case e: scala.xml.Elem => e }
res1: Seq[scala.xml.Elem] = List(<b>Test </b>)

Using .collect method, the "Foo" string is excluded from the children list.

stevedlawrence
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  • Thanks for the complete answer, the trim method was exactly what I was looking for, it also removes the trailling whitespace for xml with bigger depths. – BlueSheepToken Oct 25 '18 at 12:48
1

I checked that with this on Mac:

XML.loadString("""<a>
                   |    <b></b>
                   |</a>""").child

This results in the same behavior - which I also not understand.

However this can fix this in your code:

XML.loadString("""<a>
                   |    <b></b>
                   |</a>""").child
  .collect{ case e: Elem=> e}

This will eliminate the xml.Texts.

pme
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  • Thanks for the quick fix, but it's annoying to do this each time I need to remove the white space (and I need to do it a lot) Someone explained why, you should check it out :) – BlueSheepToken Oct 25 '18 at 12:46