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;
27
28/**
29 * An object that implements this interface contains the information
30 * needed to act as source input (XML source or transformation instructions).
31 *
32 * @since 1.4
33 */
34public interface Source {
35
36    /**
37     * Set the system identifier for this Source.
38     *
39     * <p>The system identifier is optional if the source does not
40     * get its data from a URL, but it may still be useful to provide one.
41     * The application can use a system identifier, for example, to resolve
42     * relative URIs and to include in error messages and warnings.</p>
43     *
44     * @param systemId The system identifier as a URL string.
45     */
46    public void setSystemId(String systemId);
47
48    /**
49     * Get the system identifier that was set with setSystemId.
50     *
51     * @return The system identifier that was set with setSystemId, or null
52     * if setSystemId was not called.
53     */
54    public String getSystemId();
55
56    /**
57     * Indicates whether the {@code Source} object is empty. Empty means
58     * that there is no input available from this Source.
59     *
60     * @implSpec The default implementation of this method throws
61     * {@link UnsupportedOperationException}.
62     *
63     * @return true if the {@code Source} object is empty, false otherwise
64     */
65    default boolean isEmpty() {
66        throw new UnsupportedOperationException("The isEmpty method is not supported.");
67    }
68}
69