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 38 namespace WebCore { 39 40 class EmptyNodeList FINAL : public NodeList { 41 public: create(Node & rootNode)42 static PassRefPtrWillBeRawPtr<EmptyNodeList> create(Node& rootNode) 43 { 44 return adoptRefWillBeNoop(new EmptyNodeList(rootNode)); 45 } 46 virtual ~EmptyNodeList(); 47 ownerNode()48 Node& ownerNode() const { return *m_owner; } 49 50 virtual void trace(Visitor*) OVERRIDE; 51 52 private: EmptyNodeList(Node & rootNode)53 explicit EmptyNodeList(Node& rootNode) : m_owner(rootNode) { } 54 length()55 virtual unsigned length() const OVERRIDE { return 0; } item(unsigned)56 virtual Node* item(unsigned) const OVERRIDE { return 0; } 57 isEmptyNodeList()58 virtual bool isEmptyNodeList() const OVERRIDE { return true; } 59 virtual Node* virtualOwnerNode() const OVERRIDE; 60 61 RefPtrWillBeMember<Node> m_owner; 62 }; 63 64 DEFINE_TYPE_CASTS(EmptyNodeList, NodeList, nodeList, nodeList->isEmptyNodeList(), nodeList.isEmptyNodeList()); 65 66 } // namespace WebCore 67 68 #endif // EmptyNodeList_h 69