1 /* 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. Oracle designates this 7 * particular file as subject to the "Classpath" exception as provided 8 * by Oracle in the LICENSE file that accompanied this code. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 */ 24 25 /* 26 * This file is available under and governed by the GNU General Public 27 * License version 2 only, as published by the Free Software Foundation. 28 * However, the following notice accompanied the original version of this 29 * file and, per its terms, should not be removed: 30 * 31 * Copyright (c) 2004 World Wide Web Consortium, 32 * 33 * (Massachusetts Institute of Technology, European Research Consortium for 34 * Informatics and Mathematics, Keio University). All Rights Reserved. This 35 * work is distributed under the W3C(r) Software License [1] in the hope that 36 * it will be useful, but WITHOUT ANY WARRANTY; without even the implied 37 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 38 * 39 * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231 40 */ 41 42 package org.w3c.dom.ls; 43 44 import org.w3c.dom.Node; 45 import org.w3c.dom.Element; 46 47 /** 48 * <code>LSParserFilter</code>s provide applications the ability to examine 49 * nodes as they are being constructed while parsing. As each node is 50 * examined, it may be modified or removed, or the entire parse may be 51 * terminated early. 52 * <p> At the time any of the filter methods are called by the parser, the 53 * owner Document and DOMImplementation objects exist and are accessible. 54 * The document element is never passed to the <code>LSParserFilter</code> 55 * methods, i.e. it is not possible to filter out the document element. 56 * <code>Document</code>, <code>DocumentType</code>, <code>Notation</code>, 57 * <code>Entity</code>, and <code>Attr</code> nodes are never passed to the 58 * <code>acceptNode</code> method on the filter. The child nodes of an 59 * <code>EntityReference</code> node are passed to the filter if the 60 * parameter "<a href='http://www.w3.org/TR/DOM-Level-3-Core/core.html#parameter-entities'> 61 * entities</a>" is set to <code>false</code>. Note that, as described by the parameter "<a href='http://www.w3.org/TR/DOM-Level-3-Core/core.html#parameter-entities'> 62 * entities</a>", unexpanded entity reference nodes are never discarded and are always 63 * passed to the filter. 64 * <p> All validity checking while parsing a document occurs on the source 65 * document as it appears on the input stream, not on the DOM document as it 66 * is built in memory. With filters, the document in memory may be a subset 67 * of the document on the stream, and its validity may have been affected by 68 * the filtering. 69 * <p> All default attributes must be present on elements when the elements 70 * are passed to the filter methods. All other default content must be 71 * passed to the filter methods. 72 * <p> DOM applications must not raise exceptions in a filter. The effect of 73 * throwing exceptions from a filter is DOM implementation dependent. 74 * <p>See also the <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-LS-20040407'>Document Object Model (DOM) Level 3 Load 75 and Save Specification</a>. 76 * 77 * @since 1.5 78 */ 79 public interface LSParserFilter { 80 // Constants returned by startElement and acceptNode 81 /** 82 * Accept the node. 83 */ 84 public static final short FILTER_ACCEPT = 1; 85 /** 86 * Reject the node and its children. 87 */ 88 public static final short FILTER_REJECT = 2; 89 /** 90 * Skip this single node. The children of this node will still be 91 * considered. 92 */ 93 public static final short FILTER_SKIP = 3; 94 /** 95 * Interrupt the normal processing of the document. 96 */ 97 public static final short FILTER_INTERRUPT = 4; 98 99 /** 100 * The parser will call this method after each <code>Element</code> start 101 * tag has been scanned, but before the remainder of the 102 * <code>Element</code> is processed. The intent is to allow the 103 * element, including any children, to be efficiently skipped. Note that 104 * only element nodes are passed to the <code>startElement</code> 105 * function. 106 * <br>The element node passed to <code>startElement</code> for filtering 107 * will include all of the Element's attributes, but none of the 108 * children nodes. The Element may not yet be in place in the document 109 * being constructed (it may not have a parent node.) 110 * <br>A <code>startElement</code> filter function may access or change 111 * the attributes for the Element. Changing Namespace declarations will 112 * have no effect on namespace resolution by the parser. 113 * <br>For efficiency, the Element node passed to the filter may not be 114 * the same one as is actually placed in the tree if the node is 115 * accepted. And the actual node (node object identity) may be reused 116 * during the process of reading in and filtering a document. 117 * @param elementArg The newly encountered element. At the time this 118 * method is called, the element is incomplete - it will have its 119 * attributes, but no children. 120 * @return 121 * <ul> 122 * <li> <code>FILTER_ACCEPT</code> if the <code>Element</code> should 123 * be included in the DOM document being built. 124 * </li> 125 * <li> 126 * <code>FILTER_REJECT</code> if the <code>Element</code> and all of 127 * its children should be rejected. 128 * </li> 129 * <li> <code>FILTER_SKIP</code> if the 130 * <code>Element</code> should be skipped. All of its children are 131 * inserted in place of the skipped <code>Element</code> node. 132 * </li> 133 * <li> 134 * <code>FILTER_INTERRUPT</code> if the filter wants to stop the 135 * processing of the document. Interrupting the processing of the 136 * document does no longer guarantee that the resulting DOM tree is 137 * XML well-formed. The <code>Element</code> is rejected. 138 * </li> 139 * </ul> Returning 140 * any other values will result in unspecified behavior. 141 */ 142 public short startElement(Element elementArg); 143 144 /** 145 * This method will be called by the parser at the completion of the 146 * parsing of each node. The node and all of its descendants will exist 147 * and be complete. The parent node will also exist, although it may be 148 * incomplete, i.e. it may have additional children that have not yet 149 * been parsed. Attribute nodes are never passed to this function. 150 * <br>From within this method, the new node may be freely modified - 151 * children may be added or removed, text nodes modified, etc. The state 152 * of the rest of the document outside this node is not defined, and the 153 * affect of any attempt to navigate to, or to modify any other part of 154 * the document is undefined. 155 * <br>For validating parsers, the checks are made on the original 156 * document, before any modification by the filter. No validity checks 157 * are made on any document modifications made by the filter. 158 * <br>If this new node is rejected, the parser might reuse the new node 159 * and any of its descendants. 160 * @param nodeArg The newly constructed element. At the time this method 161 * is called, the element is complete - it has all of its children 162 * (and their children, recursively) and attributes, and is attached 163 * as a child to its parent. 164 * @return 165 * <ul> 166 * <li> <code>FILTER_ACCEPT</code> if this <code>Node</code> should 167 * be included in the DOM document being built. 168 * </li> 169 * <li> 170 * <code>FILTER_REJECT</code> if the <code>Node</code> and all of its 171 * children should be rejected. 172 * </li> 173 * <li> <code>FILTER_SKIP</code> if the 174 * <code>Node</code> should be skipped and the <code>Node</code> 175 * should be replaced by all the children of the <code>Node</code>. 176 * </li> 177 * <li> 178 * <code>FILTER_INTERRUPT</code> if the filter wants to stop the 179 * processing of the document. Interrupting the processing of the 180 * document does no longer guarantee that the resulting DOM tree is 181 * XML well-formed. The <code>Node</code> is accepted and will be the 182 * last completely parsed node. 183 * </li> 184 * </ul> 185 */ 186 public short acceptNode(Node nodeArg); 187 188 /** 189 * Tells the <code>LSParser</code> what types of nodes to show to the 190 * method <code>LSParserFilter.acceptNode</code>. If a node is not shown 191 * to the filter using this attribute, it is automatically included in 192 * the DOM document being built. See <code>NodeFilter</code> for 193 * definition of the constants. The constants <code>SHOW_ATTRIBUTE</code> 194 * , <code>SHOW_DOCUMENT</code>, <code>SHOW_DOCUMENT_TYPE</code>, 195 * <code>SHOW_NOTATION</code>, <code>SHOW_ENTITY</code>, and 196 * <code>SHOW_DOCUMENT_FRAGMENT</code> are meaningless here. Those nodes 197 * will never be passed to <code>LSParserFilter.acceptNode</code>. 198 * <br> The constants used here are defined in [<a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Traversal-Range-20001113'>DOM Level 2 Traversal and Range</a>] 199 * . 200 */ 201 public int getWhatToShow(); 202 203 }