org.w3c.dom.ls.LSParserFilter Maven / Gradle / Ivy
/*
* 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.Element;
import org.w3c.dom.Node;
/**
* 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
*
* -
FILTER_ACCEPT if the Element should
* be included in the DOM document being built.
*
* -
*
FILTER_REJECT if the Element and all of
* its children should be rejected.
*
* -
FILTER_SKIP if the
* Element should be skipped. All of its children are
* inserted in place of the skipped Element node.
*
* -
*
FILTER_INTERRUPT if the filter wants to stop the
* processing of the document. Interrupting the processing of the
* document does no longer guarantee that the resulting DOM tree is
* XML well-formed. The Element is rejected.
*
*
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
*
* -
FILTER_ACCEPT if this Node should
* be included in the DOM document being built.
*
* -
*
FILTER_REJECT if the Node and all of its
* children should be rejected.
*
* -
FILTER_SKIP if the
* Node should be skipped and the Node
* should be replaced by all the children of the Node.
*
* -
*
FILTER_INTERRUPT if the filter wants to stop the
* processing of the document. Interrupting the processing of the
* document does no longer guarantee that the resulting DOM tree is
* XML well-formed. The Node is accepted and will be the
* last completely parsed node.
*
*
*/
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();
}