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org.w3c.dom.ls
public interface: LSParserFilter [javadoc | source] 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.
Field Summary
public static final  short FILTER_ACCEPT    Accept the node. 
public static final  short FILTER_REJECT    Reject the node and its children. 
public static final  short FILTER_SKIP    Skip this single node. The children of this node will still be considered. 
public static final  short FILTER_INTERRUPT    Interrupt the normal processing of the document. 
Method from org.w3c.dom.ls.LSParserFilter Summary:
acceptNode,   getWhatToShow,   startElement
Method from org.w3c.dom.ls.LSParserFilter Detail:
 public short acceptNode(Node nodeArg)
    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.
 public int getWhatToShow()
    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 short startElement(Element elementArg)
    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.