1/*
2 * Copyright (C) 2013 Apple Inc. All rights reserved.
3 * Copyright (C) 2014 Samsung Electronics. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met:
8 *
9 *     * Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *     * Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following disclaimer
13 * in the documentation and/or other materials provided with the
14 * distribution.
15 *     * Neither the name of Google Inc. nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef EmptyNodeList_h
33#define EmptyNodeList_h
34
35#include "core/dom/NodeList.h"
36#include "wtf/RefPtr.h"
37
38namespace blink {
39
40class EmptyNodeList FINAL : public NodeList {
41public:
42    static PassRefPtrWillBeRawPtr<EmptyNodeList> create(Node& rootNode)
43    {
44        return adoptRefWillBeNoop(new EmptyNodeList(rootNode));
45    }
46    virtual ~EmptyNodeList();
47
48    Node& ownerNode() const { return *m_owner; }
49
50    virtual void trace(Visitor*) OVERRIDE;
51
52private:
53    explicit EmptyNodeList(Node& rootNode) : m_owner(rootNode) { }
54
55    virtual unsigned length() const OVERRIDE { return 0; }
56    virtual Node* item(unsigned) const OVERRIDE { return 0; }
57
58    virtual bool isEmptyNodeList() const OVERRIDE { return true; }
59    virtual Node* virtualOwnerNode() const OVERRIDE;
60
61    RefPtrWillBeMember<Node> m_owner;
62};
63
64DEFINE_TYPE_CASTS(EmptyNodeList, NodeList, nodeList, nodeList->isEmptyNodeList(), nodeList.isEmptyNodeList());
65
66} // namespace blink
67
68#endif // EmptyNodeList_h
69