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 * Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package javax.xml.transform.dom;

import javax.xml.transform.Source;

import org.w3c.dom.Node;

/**

 * <p>Acts as a holder for a transformation Source tree in the

 * form of a Document Object Model (DOM) tree.</p>

 *

 * <p>Note that XSLT requires namespace support. Attempting to transform a DOM

 * that was not contructed with a namespace-aware parser may result in errors.

 * Parsers can be made namespace aware by calling

 * {@link javax.xml.parsers.DocumentBuilderFactory#setNamespaceAware(boolean awareness)}.</p>

 *

 * @author Jeff Suttor

 * @see <a href="http://www.w3.org/TR/DOM-Level-2">Document Object Model (DOM) Level 2 Specification</a>

 * @since 1.4

 */

public class DOMSource implements Source {

    /**

     * <p><code>Node</code> to serve as DOM source.</p>

     */

    private Node node;

    /**

     * <p>The base ID (URL or system ID) from where URLs

     * will be resolved.</p>

     */

    private String systemID;

    /** If {@link javax.xml.transform.TransformerFactory#getFeature}

     * returns true when passed this value as an argument,

     * the Transformer supports Source input of this type.

     */

    public static final String FEATURE =

        "http://javax.xml.transform.dom.DOMSource/feature";

    /**

     * <p>Zero-argument default constructor.  If this constructor is used, and

     * no DOM source is set using {@link #setNode(Node node)} , then the

     * <code>Transformer</code> will

     * create an empty source {@link org.w3c.dom.Document} using

     * {@link javax.xml.parsers.DocumentBuilder#newDocument()}.</p>

     *

     * @see javax.xml.transform.Transformer#transform(Source xmlSource, Result outputTarget)

     */

    public DOMSource() { }

    /**

     * Create a new input source with a DOM node.  The operation

     * will be applied to the subtree rooted at this node.  In XSLT,

     * a "/" pattern still means the root of the tree (not the subtree),

     * and the evaluation of global variables and parameters is done

     * from the root node also.

     *

     * @param n The DOM node that will contain the Source tree.

     */

    public DOMSource(Node n) {

        setNode(n);

    }

    /**

     * Create a new input source with a DOM node, and with the

     * system ID also passed in as the base URI.

     *

     * @param node The DOM node that will contain the Source tree.

     * @param systemID Specifies the base URI associated with node.

     */

    public DOMSource(Node node, String systemID) {

        setNode(node);

        setSystemId(systemID);

    }

    /**

     * Set the node that will represents a Source DOM tree.

     *

     * @param node The node that is to be transformed.

     */

    public void setNode(Node node) {

        this.node = node;

    }

    /**

     * Get the node that represents a Source DOM tree.

     *

     * @return The node that is to be transformed.

     */

    public Node getNode() {

        return node;

    }

    /**

     * Set the base ID (URL or system ID) from where URLs

     * will be resolved.

     *

     * @param systemID Base URL for this DOM tree.

     */

    @Override

    public void setSystemId(String systemID) {

        this.systemID = systemID;

    }

    /**

     * Get the base ID (URL or system ID) from where URLs

     * will be resolved.

     *

     * @return Base URL for this DOM tree.

     */

    @Override

    public String getSystemId() {

        return this.systemID;

    }

    /**

     * Indicates whether the {@code DOMSource} object is empty. Empty is

     * defined as follows:

     * <ul>

     * <li>if the system identifier and node are {@code null};

     * </li>

     * <li>if the system identifier is null, and the {@code node} has no child nodes.

     * </li>

     * </ul>

     *

     * @return true if the {@code DOMSource} object is empty, false otherwise

     */

    @Override

    public boolean isEmpty() {

        return systemID == null && (node == null || !node.hasChildNodes());

    }

}