XPath and namespaces...

Collapse
This topic is closed.
X
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • Stefan Franke
    #1

    XPath and namespaces...

    Hi,
    I've got a little bit of a problem when dealing with namespaces and XPath.

    I'm trying very basic things, like showing all the nodes of one particular
    namespace. Here is my XPath statement:
    //*[local-name() = 'buch' and namespace-uri() =
    'http://www.example.com/buecher']

    Unfortunately this doesn't work. I have found several ways to solve this
    with XSLT, but I need the pure XPath statement.

    My XML file looks like this:

    <?xml version="1.0"?>
    <!-- Dateiname: Sammlung.xml -->
    <SAMMLUNG
    xmlns:buch="htt p://www.example.com/buecher"
    xmlns:cd="http://www.example.com/cds">

    <buch:ARTIKEL Status="vorhand en">
    <buch:TITEL>T he Adventures of Huckleberry Finn</buch:TITEL>
    <buch:AUTOR>Mar k Twain</buch:AUTOR>
    <buch:PREIS>12. 75</buch:PREIS>
    </buch:ARTIKEL>
    <cd:ARTIKEL>
    <cd:TITEL>Violi nkonzert D-Dur</cd:TITEL>
    <cd:KOMPONIST>B eethoven</cd:KOMPONIST>
    <cd:PREIS>14.95 </cd:PREIS>
    </cd:ARTIKEL>
    </SAMMLUNG>


    Could anyone please give me a hint how to solve this problem?

    Thanks,
    Stefan


    Tags: None
    • Martin Honnen
      #2
      Re: XPath and namespaces...



      Stefan Franke wrote:

      [color=blue]
      > I've got a little bit of a problem when dealing with namespaces and XPath.
      >
      > I'm trying very basic things, like showing all the nodes of one particular
      > namespace. Here is my XPath statement:
      > //*[local-name() = 'buch' and namespace-uri() =
      > 'http://www.example.com/buecher']
      >
      > Unfortunately this doesn't work.[/color]

      What do you mean by "doesn't work"? Do you get an error? Which software
      are you using to test that XPath expression?

      [color=blue]
      > My XML file looks like this:
      >
      > <?xml version="1.0"?>
      > <!-- Dateiname: Sammlung.xml -->
      > <SAMMLUNG
      > xmlns:buch="htt p://www.example.com/buecher"
      > xmlns:cd="http://www.example.com/cds">
      >
      > <buch:ARTIKEL Status="vorhand en">
      > <buch:TITEL>T he Adventures of Huckleberry Finn</buch:TITEL>
      > <buch:AUTOR>Mar k Twain</buch:AUTOR>
      > <buch:PREIS>12. 75</buch:PREIS>
      > </buch:ARTIKEL>
      > <cd:ARTIKEL>
      > <cd:TITEL>Violi nkonzert D-Dur</cd:TITEL>
      > <cd:KOMPONIST>B eethoven</cd:KOMPONIST>
      > <cd:PREIS>14.95 </cd:PREIS>
      > </cd:ARTIKEL>
      > </SAMMLUNG>[/color]

      Well looking at your example XML the expression

      //*[local-name() = 'buch' and namespace-uri() =
      'http://www.example.com/buecher']

      will not find any element as the XML doesn't contain any
      <buch xmlns="http://www.example.com/buecher" />
      elements, perhaps you are looking for

      //*[local-name() = 'ARTIKEL' and namespace-uri() =
      'http://www.example.com/buecher']


      --

      Martin Honnen
      Attention Required! | Cloudflare
      http://JavaScript.FAQTs.com/

        Comment

        • Stefan Franke
          #3
          Re: XPath and namespaces...

          > perhaps you are looking for[color=blue]
          >
          > //*[local-name() = 'ARTIKEL' and namespace-uri() =
          > 'http://www.example.com/buecher']
          >[/color]

          oops, indeed I am.

          Thanks very much,
          Stefan


            Comment

            • Stefan Franke
              #4
              Re:still problems with XPath and namespaces...

              Hi,
              I'm still having troubles with XPath and namespaces.

              The XML I'm using looks like this:

              <SAMMLUNG
              xmlns:buch="htt p://www.example.com/buecher"
              xmlns:cd="http://www.example.com/cds">

              <buch:ARTIKEL Status="vorhand en">
              <buch:TITEL>T he Marble Faun</buch:TITEL>
              <buch:AUTOR>Nat haniel Hawthorne</buch:AUTOR>
              <buch:PREIS>10. 95</buch:PREIS>
              </buch:ARTIKEL>
              <cd:ARTIKEL>
              <cd:TITEL>Violi nkonzerte 1, 2 und 3</cd:TITEL>
              <cd:KOMPONIST>M ozart</cd:KOMPONIST>
              <cd:PREIS>16.49 </cd:PREIS>
              </cd:ARTIKEL>
              </SAMMLUNG>


              If I want to display e.g. all the CDs of Mozart, I would do something like
              this if I wouldn't have to deal with namespaces:

              string(//*/TITEL[following-sibling::KOMPON IST='Mozart'])

              My suggestion when dealing with namespaces would be something like this (but
              it doesn't work, as there is no TITEL-element anywhere, but I don't know how
              to get it in there):

              string(//*[local-name()='ARTIKEL ' and
              namespace-uri()='http://www.example.com/cds']/*[string(local-name()='KOMPONI ST')
              = 'Mozart'])

              Anyway, as I said before, that doesn't work. Could someone please help me
              with that?

              Thanks,
              Stefan


                Comment

                • Martin Honnen
                  #5
                  Re: still problems with XPath and namespaces...



                  Stefan Franke wrote:

                  [color=blue]
                  > The XML I'm using looks like this:
                  >
                  > <SAMMLUNG
                  > xmlns:buch="htt p://www.example.com/buecher"
                  > xmlns:cd="http://www.example.com/cds">
                  >
                  > <buch:ARTIKEL Status="vorhand en">
                  > <buch:TITEL>T he Marble Faun</buch:TITEL>
                  > <buch:AUTOR>Nat haniel Hawthorne</buch:AUTOR>
                  > <buch:PREIS>10. 95</buch:PREIS>
                  > </buch:ARTIKEL>
                  > <cd:ARTIKEL>
                  > <cd:TITEL>Violi nkonzerte 1, 2 und 3</cd:TITEL>
                  > <cd:KOMPONIST>M ozart</cd:KOMPONIST>
                  > <cd:PREIS>16.49 </cd:PREIS>
                  > </cd:ARTIKEL>
                  > </SAMMLUNG>
                  >
                  >
                  > If I want to display e.g. all the CDs of Mozart, I would do something like
                  > this if I wouldn't have to deal with namespaces:
                  >
                  > string(//*/TITEL[following-sibling::KOMPON IST='Mozart'])[/color]

                  Not really, if you apply the string function to a nodeset then you get
                  the string value of the first node in document order so the above
                  doesn't give you all CD titles but only one.
                  [color=blue]
                  > My suggestion when dealing with namespaces would be something like this (but
                  > it doesn't work, as there is no TITEL-element anywhere, but I don't know how
                  > to get it in there):
                  >
                  > string(//*[local-name()='ARTIKEL ' and
                  > namespace-uri()='http://www.example.com/cds']/*[string(local-name()='KOMPONI ST')
                  > = 'Mozart'])[/color]

                  How are you evaluating your XPaths? You should simply be able to declare
                  prefixes for the namespaces and then use e.g.
                  //prefix:TITLE
                  instead of going to the pain of using namespace-uri comparisons.
                  So I think you should better tell us about the software you are using to
                  evaluate XPaths and then probably someone can tell you how to use
                  namespace prefixes bound to namespaces when evaluating XPath expressions.

                  --

                  Martin Honnen
                  Attention Required! | Cloudflare
                  http://JavaScript.FAQTs.com/

                    Comment

                    • Stefan Franke
                      #6
                      Re: still problems with XPath and namespaces...

                      > How are you evaluating your XPaths? You should simply be able to declare[color=blue]
                      > prefixes for the namespaces and then use e.g.
                      > //prefix:TITLE[/color]


                      Hi Martin,
                      I'm using FiveSight's XPathTester (Version 1.4 for Saxon - 3 December 2001).
                      When I try something like "//*/cd:TITEL" an error message comes up and tells
                      me that 'Prefix cd has not been declared'. So I thought, oh well, I have to
                      find a way around this problem. Am I wrong in thinking that?

                      regards,
                      Stefan


                        Comment

                        • Martin Honnen
                          #7
                          Re: still problems with XPath and namespaces...



                          Stefan Franke wrote:

                          [color=blue]
                          > I'm using FiveSight's XPathTester (Version 1.4 for Saxon - 3 December 2001).
                          > When I try something like "//*/cd:TITEL" an error message comes up and tells
                          > me that 'Prefix cd has not been declared'. So I thought, oh well, I have to
                          > find a way around this problem. Am I wrong in thinking that?[/color]

                          No, you need to bind that prefix to the proper namespace but an XPath
                          tool should give you a way to do that before evaluating an expression.
                          I don't know FiveSight's XPathTester and it seems it is no longer
                          available on their web site.
                          Saxon 6.5 as documented here
                          <http://saxon.sourcefor ge.net/saxon6.5.3/api-guide.html#Expr essions>
                          has a method
                          declareNamespac e
                          in its XPath API so with Java and Saxon it should be possible to bind
                          prfixes to namespaces before evaluating an expression.



                          --

                          Martin Honnen
                          Attention Required! | Cloudflare
                          http://JavaScript.FAQTs.com/

                            Comment

                            Previous template Next
                            Working...