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 Summary
Modifier and Type | Field | Description |
---|---|---|
static short | FILTER_ACCEPT | Accept the node. |
static short | FILTER_REJECT | Reject the node. |
static short | FILTER_SKIP | Skip this single node. |
static int | SHOW_ALL | Show all |
static int | SHOW_ATTRIBUTE | Show |
static int | SHOW_CDATA_SECTION | Show |
static int | SHOW_COMMENT | Show |
static int | SHOW_DOCUMENT | Show |
static int | SHOW_DOCUMENT_FRAGMENT | Show |
static int | SHOW_DOCUMENT_TYPE | Show |
static int | SHOW_ELEMENT | Show |
static int | SHOW_ENTITY | Show |
static int | SHOW_ENTITY_REFERENCE | Show |
static int | SHOW_NOTATION | Show |
static int | SHOW_PROCESSING_INSTRUCTION | Show |
static int | SHOW_TEXT | Show |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
short | acceptNode(Node n) | Test whether a specified node is visible in the logical view of a |
Field Detail
FILTER_ACCEPT
static final short FILTER_ACCEPT
Accept the node. Navigation methods defined for NodeIterator
or TreeWalker
will return this node.
- See Also:
- 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
.
- See Also:
- 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.
- See Also:
- Constant Field Values
SHOW_ALL
static final int SHOW_ALL
Show all Nodes
.
- See Also:
- Constant Field Values
SHOW_ELEMENT
static final int SHOW_ELEMENT
Show Element
nodes.
- See Also:
- Constant Field Values
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.
- See Also:
- Constant Field Values
SHOW_TEXT
static final int SHOW_TEXT
Show Text
nodes.
- See Also:
- Constant Field Values
SHOW_CDATA_SECTION
static final int SHOW_CDATA_SECTION
Show CDATASection
nodes.
- See Also:
- Constant Field Values
SHOW_ENTITY_REFERENCE
static final int SHOW_ENTITY_REFERENCE
Show EntityReference
nodes.
- See Also:
- Constant Field Values
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.
- See Also:
- Constant Field Values
SHOW_PROCESSING_INSTRUCTION
static final int SHOW_PROCESSING_INSTRUCTION
Show ProcessingInstruction
nodes.
- See Also:
- Constant Field Values
SHOW_COMMENT
static final int SHOW_COMMENT
Show Comment
nodes.
- See Also:
- Constant Field Values
SHOW_DOCUMENT
static final int SHOW_DOCUMENT
Show Document
nodes.
- See Also:
- Constant Field Values
SHOW_DOCUMENT_TYPE
static final int SHOW_DOCUMENT_TYPE
Show DocumentType
nodes.
- See Also:
- Constant Field Values
SHOW_DOCUMENT_FRAGMENT
static final int SHOW_DOCUMENT_FRAGMENT
Show DocumentFragment
nodes.
- See Also:
- Constant Field Values
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.
- See Also:
- Constant Field Values
Method Detail
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.