/* * Copyright (c) 2004 World Wide Web Consortium, * * (Massachusetts Institute of Technology, European Research Consortium for * Informatics and Mathematics, Keio University). All Rights Reserved. This * work is distributed under the W3C(r) Software License [1] in the hope that * it will be useful, but WITHOUT ANY WARRANTY; without even the implied * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231 */ package org.w3c.dom.ls; import org.w3c.dom.Node; import org.w3c.dom.Element; /** * LSParserFilters provide applications the ability to examine * nodes as they are being constructed while parsing. As each node is * examined, it may be modified or removed, or the entire parse may be * terminated early. *

At the time any of the filter methods are called by the parser, the * owner Document and DOMImplementation objects exist and are accessible. * The document element is never passed to the LSParserFilter * methods, i.e. it is not possible to filter out the document element. * Document, DocumentType, Notation, * Entity, and Attr nodes are never passed to the * acceptNode method on the filter. The child nodes of an * EntityReference node are passed to the filter if the * parameter " * entities" is set to false. Note that, as described by the parameter " * entities", unexpanded entity reference nodes are never discarded and are always * passed to the filter. *

All validity checking while parsing a document occurs on the source * document as it appears on the input stream, not on the DOM document as it * is built in memory. With filters, the document in memory may be a subset * of the document on the stream, and its validity may have been affected by * the filtering. *

All default attributes must be present on elements when the elements * are passed to the filter methods. All other default content must be * passed to the filter methods. *

DOM applications must not raise exceptions in a filter. The effect of * throwing exceptions from a filter is DOM implementation dependent. *

See also the Document Object Model (DOM) Level 3 Load and Save Specification. */ public interface LSParserFilter { // Constants returned by startElement and acceptNode /** * Accept the node. */ public static final short FILTER_ACCEPT = 1; /** * Reject the node and its children. */ public static final short FILTER_REJECT = 2; /** * Skip this single node. The children of this node will still be * considered. */ public static final short FILTER_SKIP = 3; /** * Interrupt the normal processing of the document. */ public static final short FILTER_INTERRUPT = 4; /** * The parser will call this method after each Element start * tag has been scanned, but before the remainder of the * Element is processed. The intent is to allow the * element, including any children, to be efficiently skipped. Note that * only element nodes are passed to the startElement * function. *
The element node passed to startElement for filtering * will include all of the Element's attributes, but none of the * children nodes. The Element may not yet be in place in the document * being constructed (it may not have a parent node.) *
A startElement filter function may access or change * the attributes for the Element. Changing Namespace declarations will * have no effect on namespace resolution by the parser. *
For efficiency, the Element node passed to the filter may not be * the same one as is actually placed in the tree if the node is * accepted. And the actual node (node object identity) may be reused * during the process of reading in and filtering a document. * @param elementArg The newly encountered element. At the time this * method is called, the element is incomplete - it will have its * attributes, but no children. * @return *

Returning * any other values will result in unspecified behavior. */ public short startElement(Element elementArg); /** * This method will be called by the parser at the completion of the * parsing of each node. The node and all of its descendants will exist * and be complete. The parent node will also exist, although it may be * incomplete, i.e. it may have additional children that have not yet * been parsed. Attribute nodes are never passed to this function. *
From within this method, the new node may be freely modified - * children may be added or removed, text nodes modified, etc. The state * of the rest of the document outside this node is not defined, and the * affect of any attempt to navigate to, or to modify any other part of * the document is undefined. *
For validating parsers, the checks are made on the original * document, before any modification by the filter. No validity checks * are made on any document modifications made by the filter. *
If this new node is rejected, the parser might reuse the new node * and any of its descendants. * @param nodeArg The newly constructed element. At the time this method * is called, the element is complete - it has all of its children * (and their children, recursively) and attributes, and is attached * as a child to its parent. * @return * */ public short acceptNode(Node nodeArg); /** * Tells the LSParser what types of nodes to show to the * method LSParserFilter.acceptNode. If a node is not shown * to the filter using this attribute, it is automatically included in * the DOM document being built. See NodeFilter for * definition of the constants. The constants SHOW_ATTRIBUTE * , SHOW_DOCUMENT, SHOW_DOCUMENT_TYPE, * SHOW_NOTATION, SHOW_ENTITY, and * SHOW_DOCUMENT_FRAGMENT are meaningless here. Those nodes * will never be passed to LSParserFilter.acceptNode. *
The constants used here are defined in [DOM Level 2 Traversal and Range] * . */ public int getWhatToShow(); }