1/*
2 * Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package javax.xml.transform.dom;
27
28import javax.xml.transform.Source;
29
30import org.w3c.dom.Node;
31
32/**
33 * <p>Acts as a holder for a transformation Source tree in the
34 * form of a Document Object Model (DOM) tree.</p>
35 *
36 * <p>Note that XSLT requires namespace support. Attempting to transform a DOM
37 * that was not contructed with a namespace-aware parser may result in errors.
38 * Parsers can be made namespace aware by calling
39 * {@link javax.xml.parsers.DocumentBuilderFactory#setNamespaceAware(boolean awareness)}.</p>
40 *
41 * @author <a href="Jeff.Suttor@Sun.com">Jeff Suttor</a>
42 * @see <a href="http://www.w3.org/TR/DOM-Level-2">Document Object Model (DOM) Level 2 Specification</a>
43 * @since 1.4
44 */
45public class DOMSource implements Source {
46
47    /**
48     * <p><code>Node</code> to serve as DOM source.</p>
49     */
50    private Node node;
51
52    /**
53     * <p>The base ID (URL or system ID) from where URLs
54     * will be resolved.</p>
55     */
56    private String systemID;
57
58    /** If {@link javax.xml.transform.TransformerFactory#getFeature}
59     * returns true when passed this value as an argument,
60     * the Transformer supports Source input of this type.
61     */
62    public static final String FEATURE =
63        "http://javax.xml.transform.dom.DOMSource/feature";
64
65    /**
66     * <p>Zero-argument default constructor.  If this constructor is used, and
67     * no DOM source is set using {@link #setNode(Node node)} , then the
68     * <code>Transformer</code> will
69     * create an empty source {@link org.w3c.dom.Document} using
70     * {@link javax.xml.parsers.DocumentBuilder#newDocument()}.</p>
71     *
72     * @see javax.xml.transform.Transformer#transform(Source xmlSource, Result outputTarget)
73     */
74    public DOMSource() { }
75
76    /**
77     * Create a new input source with a DOM node.  The operation
78     * will be applied to the subtree rooted at this node.  In XSLT,
79     * a "/" pattern still means the root of the tree (not the subtree),
80     * and the evaluation of global variables and parameters is done
81     * from the root node also.
82     *
83     * @param n The DOM node that will contain the Source tree.
84     */
85    public DOMSource(Node n) {
86        setNode(n);
87    }
88
89    /**
90     * Create a new input source with a DOM node, and with the
91     * system ID also passed in as the base URI.
92     *
93     * @param node The DOM node that will contain the Source tree.
94     * @param systemID Specifies the base URI associated with node.
95     */
96    public DOMSource(Node node, String systemID) {
97        setNode(node);
98        setSystemId(systemID);
99    }
100
101    /**
102     * Set the node that will represents a Source DOM tree.
103     *
104     * @param node The node that is to be transformed.
105     */
106    public void setNode(Node node) {
107        this.node = node;
108    }
109
110    /**
111     * Get the node that represents a Source DOM tree.
112     *
113     * @return The node that is to be transformed.
114     */
115    public Node getNode() {
116        return node;
117    }
118
119    /**
120     * Set the base ID (URL or system ID) from where URLs
121     * will be resolved.
122     *
123     * @param systemID Base URL for this DOM tree.
124     */
125    @Override
126    public void setSystemId(String systemID) {
127        this.systemID = systemID;
128    }
129
130    /**
131     * Get the base ID (URL or system ID) from where URLs
132     * will be resolved.
133     *
134     * @return Base URL for this DOM tree.
135     */
136    @Override
137    public String getSystemId() {
138        return this.systemID;
139    }
140
141    /**
142     * Indicates whether the {@code DOMSource} object is empty. Empty is
143     * defined as follows:
144     * <ul>
145     * <li>if the system identifier and node are {@code null};
146     * </li>
147     * <li>if the system identifier is null, and the {@code node} has no child nodes.
148     * </li>
149     * </ul>
150     *
151     * @return true if the {@code DOMSource} object is empty, false otherwise
152     */
153    @Override
154    public boolean isEmpty() {
155        return systemID == null && (node == null || !node.hasChildNodes());
156    }
157}
158