Java XML QName Get getQName(@Nonnull final Element aElement)

Description

Get the QName of the passed element.

License

Apache License

Parameter

Parameter	Description
aElement	The element to be used. May not be <code>null</code>.

Return

The created .

Declaration

@Nonnull
public static QName getQName(@Nonnull final Element aElement) 

Method Source Code

//package com.java2s;
/**//from  ww  w.  j  av  a2s .  c o m
 * Copyright (C) 2014-2017 Philip Helger (www.helger.com)
 * philip[at]helger[dot]com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import javax.xml.XMLConstants;
import javax.xml.namespace.QName;

import org.w3c.dom.Document;
import org.w3c.dom.Element;

import org.w3c.dom.Node;

public class Main {
    /**
     * Get the QName of the passed element. If the passed element has no namespace
     * URI, only the tag name is used. Otherwise namespace URI, local name and
     * prefix are used.
     *
     * @param aElement
     *        The element to be used. May not be <code>null</code>.
     * @return The created {@link QName}.
     * @since 8.4.1
     */
    @Nonnull
    public static QName getQName(@Nonnull final Element aElement) {
        final String sNamespaceURI = aElement.getNamespaceURI();
        if (sNamespaceURI == null)
            return new QName(aElement.getTagName());
        return new QName(sNamespaceURI, aElement.getLocalName(), getPrefix(aElement));
    }

    @Nullable
    public static String getNamespaceURI(@Nullable final Node aNode) {
        if (aNode instanceof Document) {
            // Recurse into document element
            return getNamespaceURI(((Document) aNode).getDocumentElement());
        }
        if (aNode != null)
            return aNode.getNamespaceURI();
        return null;
    }

    /**
     * Get the namespace prefix of the passed element in a safe way.
     *
     * @param aElement
     *        The element to be queried. May be <code>null</code>.
     * @return {@link XMLConstants#DEFAULT_NS_PREFIX} or the provided prefix.
     *         Never <code>null</code>.
     * @since 8.4.1
     */
    @Nonnull
    public static String getPrefix(@Nullable final Element aElement) {
        final String sPrefix = aElement == null ? null : aElement.getPrefix();
        return sPrefix == null ? XMLConstants.DEFAULT_NS_PREFIX : sPrefix;
    }

    @Nullable
    public static Element getDocumentElement(@Nullable final Node aNode) {
        final Document aDoc = getOwnerDocument(aNode);
        return aDoc == null ? null : aDoc.getDocumentElement();
    }

    /**
     * Get the owner document of the passed node. If the node itself is a
     * document, only a cast is performed.
     *
     * @param aNode
     *        The node to get the document from. May be <code>null</code>.
     * @return <code>null</code> if the passed node was <code>null</code>.
     */
    @Nullable
    public static Document getOwnerDocument(@Nullable final Node aNode) {
        return aNode == null ? null : aNode instanceof Document ? (Document) aNode : aNode.getOwnerDocument();
    }
}

Related

1. getElementQName(Element xml)
2. getElementQName(final Element el)
3. getElements(Node context, QName qname)
4. getName(QName qName)
5. getName(QName qname)
6. getQName(Class klass)
7. getQName(Element el)
8. getQName(Element xml)
9. getQName(final String name)