Generating part of XML with namespaces with XOM

Question

Though the description looks like really long, its actually quite straightforward.

What I need

I have the following xml document

<?xml version="1.0" encoding="UTF-8"?>
<atom:feed xmlns:opensearch="http://a9.com/-/spec/opensearch/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:atom="http://www.w3.org/2005/Atom" type="application/atom+xml;type=feed">
  <atom:link rel="self" href="http://hostname/thirdparty/playlist"/>
  <atom:id>vuter id</atom:id>
  <atom:title>Untitled</atom:title>
  <opensearch:totalResults>249</opensearch:totalResults>
  <opensearch:startIndex>1</opensearch:startIndex>
  <opensearch:itemsPerPage>249</opensearch:itemsPerPage>
  <atom:entry type="application/atom+xml;type=entry">
    <atom:id>12345678</atom:id>
    <atom:title>Playlist example 1</atom:title>
    <atom:link rel="self" type="application/atom+xml;type=entry" href="http://hostname/thirdparty/playlist/2101211130000011141"/>
    <dcterms:identifier>2101211130000011141</dcterms:identifier>
  </atom:entry>
  <atom:entry type="application/atom+xml;type=entry">
    <atom:id>12345678</atom:id>
    <atom:title>Playlist example 2</atom:title>
    <atom:link rel="self" type="application/atom+xml;type=entry" href="http://hostname/thirdparty/playlist/2101211090000000341"/>
    <dcterms:identifier>2101211090000000341</dcterms:identifier>
  </atom:entry>
</atom:feed>

Notice that the xml is containing basically three namespaces

Atom: http://www.w3.org/2005/Atom
dcterms: http://purl.org/dc/terms/
opensearch: http://a9.com/-/spec/opensearch/1.1/

Now I need to generate another xml document of a single atom:entry node. Like below

<atom:entry type="application/atom+xml;type=entry" xmlns:opensearch="http://a9.com/-/spec/opensearch/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:atom="http://www.w3.org/2005/Atom">
    <atom:id>12345678</atom:id>
    <atom:title>Playlist example 1</atom:title>
    <atom:link rel="self" type="application/atom+xml;type=entry" href="http://hostname/thirdparty/playlist/2101211130000011141"/>
    <dcterms:identifier>2101211130000011141</dcterms:identifier>
</atom:entry>

What Im getting

I am using XOM and so far ive tried with

Element rootElem = new Builder().build(ins).getRootElement();
xc = XPathContext.makeNamespaceContext(rootElem);    
Element firstEntry = (Element) rootElem.query("atom:entry", xc).get(0); 
Document doc = new Document((Element)firstEntry.copy());
System.out.println(doc.toXML());

And Im getting following xml with only one namespace declaration. Like below.

<?xml version="1.0"?>
<atom:entry xmlns:atom="http://www.w3.org/2005/Atom" type="application/atom+xml;type=entry">
    <atom:id>12345678</atom:id>
    <atom:title>Playlist example 1</atom:title>
    <atom:link rel="self" type="application/atom+xml;type=entry" href="http://hostname/thirdparty/playlist/2101211130000011141" />
    <dcterms:identifier xmlns:dcterms="http://purl.org/dc/terms/">2101211130000011141</dcterms:identifier>
</atom:entry>

Problem

Its containning only Atom namespace :( Hence its not a valid XML. Because it has a child node dcterms:identifier whose namespace is missing.

I need help badly to get out of this problem. Looking forward for any help.

Mircea · Accepted Answer · 2013-01-11T15:45:35.607

There is no a problem. The dcterms namespace is declared where is needed: in the dcterms:identifier tag

<dcterms:identifier xmlns:dcterms="http://purl.org/dc/terms/">

In fact, the xml you expect and the one you get are the same. The fact that the namespaces are not declare in the same place does not affect the meaning of the xml content.

=======UPDATE========

I would advise to solve the real problem, ie the fact that your system does not accept valid xmls (or it does not interpret them correctly). As a fix for your situation try the following piece of code:

Element rootElem = new Builder().build(ins).getRootElement();
XPathContext xc = XPathContext.makeNamespaceContext(rootElem);    
Element firstEntry = (Element) rootElem.query("atom:entry", xc).get(0); 
Document doc = new Document((Element)firstEntry.copy());
Element root = doc.getRootElement();
recursive(root,root);

static void recursive(Element root, Element child){
        root.addNamespaceDeclaration(child.getNamespacePrefix(), child.getNamespaceURI());
        if (child.getChildElements().size()>0){
            int i = child.getChildElements().size();
            for (int k=0;k<i;k++){
                recursive(root,child.getChildElements().get(k));
            }
        }
    }

Basically the code above goes through all the children, identifies there namespace and adds it to the root as namespace declaration. I have tried it and worked. I hope it will act as a fix for your problem

Ya you are right. But the problem is the system, im working with, expects all the namespace declarations at the root element. Not with that specific element. So i need a way to move the declaration at the root node. — Samiron, Jan 11 '13 at 15:01
Completely agreed with you. No one would be happier than me if I could solve "the real problem". But its something out of my scope. Anyway, your solution seems really promising. I will try it out. I will get back on next Monday. — Samiron, Jan 11 '13 at 16:49

score 1 · Answer 2 · answered Apr 24 '13 at 09:54

1

You want

doc.getRootElement().addNamespaceDeclaration("dcterms", "http://purl.org/dc/terms/");

answered Apr 24 '13 at 09:54

Elliotte Rusty Harold

963
7
15

Generating part of XML with namespaces with XOM

What I need

What Im getting

Problem

2 Answers2