title: XML namespace defaulting/inheritance
body: <p>In the below XML snippet what are the namespaces of a, c, d and e? Reference to documentation or specifications would be appreciated.</p>
  
  <pre><code>&lt;a xmlns="http://domain/a"&gt;
      &lt;pre:b xmlns:pre="http://domain/b"&gt;
          &lt;c/&gt;
          &lt;d xmlns=""&gt;
              &lt;e/&gt;
          &lt;/d&gt;
      &lt;/pre:b&gt;
  &lt;/a&gt;
  </code></pre>
  
  <p>Also, what Java frameworks respect the official namespace defaulting? I have tride org.w2c.* DOM packages, however it does not seem to resolve the namespace URI correctly? For example, something with similar functionality to.</p>
  
  <pre><code>String namespace = DocumentParser.parse().
                      getElement("a").
                      getElement("b").
                      getElement("c").
                      getNamespaceURI();
  </code></pre>