public interface

NodeFilter

org.w3c.dom.traversal.NodeFilter
Known Indirect Subclasses

Class Overview

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.

Summary

Constants
short FILTER_ACCEPT Accept the node.
short FILTER_REJECT Reject the node.
short FILTER_SKIP Skip this single node.
int SHOW_ALL Show all Nodes.
int SHOW_ATTRIBUTE Show Attr nodes.
int SHOW_CDATA_SECTION Show CDATASection nodes.
int SHOW_COMMENT Show Comment nodes.
int SHOW_DOCUMENT Show Document nodes.
int SHOW_DOCUMENT_FRAGMENT Show DocumentFragment nodes.
int SHOW_DOCUMENT_TYPE Show DocumentType nodes.
int SHOW_ELEMENT Show Element nodes.
int SHOW_ENTITY Show Entity nodes.
int SHOW_ENTITY_REFERENCE Show EntityReference nodes.
int SHOW_NOTATION Show Notation nodes.
int SHOW_PROCESSING_INSTRUCTION Show ProcessingInstruction nodes.
int SHOW_TEXT Show Text nodes.
Public Methods
abstract short acceptNode(Node n)
Test whether a specified node is visible in the logical view of a TreeWalker or NodeIterator.

Constants

public static final short FILTER_ACCEPT

Accept the node. Navigation methods defined for NodeIterator or TreeWalker will return this node.

Constant Value: 1 (0x00000001)

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.

Constant Value: 2 (0x00000002)

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.

Constant Value: 3 (0x00000003)

public static final int SHOW_ALL

Show all Nodes.

Constant Value: -1 (0xffffffff)

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.

Constant Value: 2 (0x00000002)

public static final int SHOW_CDATA_SECTION

Show CDATASection nodes.

Constant Value: 8 (0x00000008)

public static final int SHOW_COMMENT

Show Comment nodes.

Constant Value: 128 (0x00000080)

public static final int SHOW_DOCUMENT

Show Document nodes.

Constant Value: 256 (0x00000100)

public static final int SHOW_DOCUMENT_FRAGMENT

Show DocumentFragment nodes.

Constant Value: 1024 (0x00000400)

public static final int SHOW_DOCUMENT_TYPE

Show DocumentType nodes.

Constant Value: 512 (0x00000200)

public static final int SHOW_ELEMENT

Show Element nodes.

Constant Value: 1 (0x00000001)

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.

Constant Value: 32 (0x00000020)

public static final int SHOW_ENTITY_REFERENCE

Show EntityReference nodes.

Constant Value: 16 (0x00000010)

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.

Constant Value: 2048 (0x00000800)

public static final int SHOW_PROCESSING_INSTRUCTION

Show ProcessingInstruction nodes.

Constant Value: 64 (0x00000040)

public static final int SHOW_TEXT

Show Text nodes.

Constant Value: 4 (0x00000004)

Public Methods

public abstract short acceptNode (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.)

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