getroot.html
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<TITLE>Getting the Root Element in a DOM Document
(Java Developers Almanac Example)
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<h3>
e1071.
Getting the Root Element in a DOM Document</h3>
The root element of an XML file is not the same as the root element of
a DOM document. In particular, the XML root element is a child of the
DOM's root element. The reason is that the XML root element can have
siblings, such as a <code>DocumentType</code> or a <code>Comment</code> node. The XML
root node can be found by looking for an element node among the
children of the DOM's root node. However, there is a convenient
method, <code>Document.getDocumentElement()</code>, that does the same thing.
This example demonstrates both methods:
<pre>
// Create a document; this method is implemented in
// <a href="../javax.xml.parsers/BasicDom.html" class="eglink"><font size="-1"><b>e510</b> The Quintessential Program to Create a DOM Document from an XML File</font></a>
Document doc = <font color="#0066ff"><i>parseXmlFile</i></font>(<font color="#0066ff"><i>"infilename.xml"</i></font>, <font color="#0066ff"><i>false</i></font>);
Element root = null;
// Get the XML root node by examining the children nodes
NodeList list = doc.getChildNodes();
for (int i=0; i<list.getLength(); i++) {
if (list.item(i) instanceof Element) {
root = (Element)list.item(i);
break;
}
}
// Get the XML root node the easy way
root = doc.getDocumentElement();
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Related Examples
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e527. <a class="eglink" href="GetNode.html?l=rel">
Getting a Node Relative to Another Node in a DOM Document
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e528. <a class="eglink" href="GetNote.html?l=rel">
Getting the Notations in a DOM Document
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<br>
e529. <a class="eglink" href="GetDecEntity.html?l=rel">
Getting the Declared Entities in a DOM Document
</a>
<br>
e530. <a class="eglink" href="GetEntityRef.html?l=rel">
Getting the Value of an Entity Reference in a DOM Document
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See also:
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Adding%20and%20Removing%20Nodes">
Adding and Removing Nodes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Element%20Attributes">
Element Attributes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Elements">
Elements
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#Text%20Nodes">
Text Nodes
</a>
<a class="eglink" href="/egs/org.w3c.dom/pkg.html?l=rel#XPath">
XPath
</a>
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