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NodeFilter.javaAPI DocJava SE 5 API6442Fri Aug 26 14:58:42 BST 2005org.w3c.dom.traversal

NodeFilter

public interface NodeFilter
Filters are objects that know how to "filter out" nodes. If a NodeIterator or TreeWalker is given a NodeFilter, it applies the filter before it returns the next node. If the filter says to accept the node, the traversal logic returns it; otherwise, traversal looks for the next node and pretends that the node that was rejected was not there.

The DOM does not provide any filters. NodeFilter is just an interface that users can implement to provide their own filters.

NodeFilters do not need to know how to traverse from node to node, nor do they need to know anything about the data structure that is being traversed. This makes it very easy to write filters, since the only thing they have to know how to do is evaluate a single node. One filter may be used with a number of different kinds of traversals, encouraging code reuse.

See also the Document Object Model (DOM) Level 2 Traversal and Range Specification.

since
DOM Level 2

Fields Summary
public static final short
FILTER_ACCEPT
Accept the node. Navigation methods defined for NodeIterator or TreeWalker will return this node.
public static final short
FILTER_REJECT
Reject the node. Navigation methods defined for NodeIterator or TreeWalker will not return this node. For TreeWalker, the children of this node will also be rejected. NodeIterators treat this as a synonym for FILTER_SKIP.
public static final short
FILTER_SKIP
Skip this single node. Navigation methods defined for NodeIterator or TreeWalker will not return this node. For both NodeIterator and TreeWalker, the children of this node will still be considered.
public static final int
SHOW_ALL
Show all Nodes.
public static final int
SHOW_ELEMENT
Show Element nodes.
public static final int
SHOW_ATTRIBUTE
Show Attr nodes. This is meaningful only when creating an NodeIterator or TreeWalker with an attribute node as its root; in this case, it means that the attribute node will appear in the first position of the iteration or traversal. Since attributes are never children of other nodes, they do not appear when traversing over the document tree.
public static final int
SHOW_TEXT
Show Text nodes.
public static final int
SHOW_CDATA_SECTION
Show CDATASection nodes.
public static final int
SHOW_ENTITY_REFERENCE
Show EntityReference nodes.
public static final int
SHOW_ENTITY
Show Entity nodes. This is meaningful only when creating an NodeIterator or TreeWalker with an Entity node as its root; in this case, it means that the Entity node will appear in the first position of the traversal. Since entities are not part of the document tree, they do not appear when traversing over the document tree.
public static final int
SHOW_PROCESSING_INSTRUCTION
Show ProcessingInstruction nodes.
public static final int
SHOW_COMMENT
Show Comment nodes.
public static final int
SHOW_DOCUMENT
Show Document nodes.
public static final int
SHOW_DOCUMENT_TYPE
Show DocumentType nodes.
public static final int
SHOW_DOCUMENT_FRAGMENT
Show DocumentFragment nodes.
public static final int
SHOW_NOTATION
Show Notation nodes. This is meaningful only when creating an NodeIterator or TreeWalker with a Notation node as its root; in this case, it means that the Notation node will appear in the first position of the traversal. Since notations are not part of the document tree, they do not appear when traversing over the document tree.
Constructors Summary
Methods Summary
public shortacceptNode(org.w3c.dom.Node n)
Test whether a specified node is visible in the logical view of a TreeWalker or NodeIterator. This function will be called by the implementation of TreeWalker and NodeIterator; it is not normally called directly from user code. (Though you could do so if you wanted to use the same filter to guide your own application logic.)

param
n The node to check to see if it passes the filter or not.
return
A constant to determine whether the node is accepted, rejected, or skipped, as defined above.