Module java.xml
Package org.w3c.dom.traversal

Interface NodeFilter

All Known Subinterfaces:
LSSerializerFilter
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:
9, DOM Level 2

  • Field Details

    • FILTER_ACCEPT

      static final short FILTER_ACCEPT
      Accept the node. Navigation methods defined for NodeIterator or TreeWalker will return this node.
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      Constant Field Values

    • FILTER_REJECT

      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.
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      Constant Field Values

    • FILTER_SKIP

      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.
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      Constant Field Values

    • SHOW_ALL

      static final int SHOW_ALL
      Show all Nodes.
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    • SHOW_ELEMENT

      static final int SHOW_ELEMENT
      Show Element nodes.
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    • SHOW_ATTRIBUTE

      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.
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    • SHOW_TEXT

      static final int SHOW_TEXT
      Show Text nodes.
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    • SHOW_CDATA_SECTION

      static final int SHOW_CDATA_SECTION
      Show CDATASection nodes.
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    • SHOW_ENTITY_REFERENCE

      static final int SHOW_ENTITY_REFERENCE
      Show EntityReference nodes.
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    • SHOW_ENTITY

      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.
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    • SHOW_PROCESSING_INSTRUCTION

      static final int SHOW_PROCESSING_INSTRUCTION
      Show ProcessingInstruction nodes.
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    • SHOW_COMMENT

      static final int SHOW_COMMENT
      Show Comment nodes.
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    • SHOW_DOCUMENT

      static final int SHOW_DOCUMENT
      Show Document nodes.
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    • SHOW_DOCUMENT_TYPE

      static final int SHOW_DOCUMENT_TYPE
      Show DocumentType nodes.
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    • SHOW_DOCUMENT_FRAGMENT

      static final int SHOW_DOCUMENT_FRAGMENT
      Show DocumentFragment nodes.
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    • SHOW_NOTATION

      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.
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      Constant Field Values

  • Method Details

    • acceptNode

      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.