org.apache.xml.dtm
Interface DTMFilter

public interface DTMFilter

Simple filter for doing node tests. Note the semantics of this are somewhat different that the DOM's NodeFilter.

Field Summary

static int	SHOW_ALL Show all Nodes.
static int	SHOW_ATTRIBUTE Show Attr nodes.
static int	SHOW_BYFUNCTION Special bit for filters implementing match patterns starting with a function.
static int	SHOW_CDATA_SECTION Show CDATASection nodes.
static int	SHOW_COMMENT Show Comment nodes.
static int	SHOW_DOCUMENT Show Document nodes.
static int	SHOW_DOCUMENT_FRAGMENT Show DocumentFragment nodes.
static int	SHOW_DOCUMENT_TYPE Show DocumentType nodes.
static int	SHOW_ELEMENT Show Element nodes.
static int	SHOW_ENTITY Show Entity nodes.
static int	SHOW_ENTITY_REFERENCE Show EntityReference nodes.
static int	SHOW_NAMESPACE This bit instructs the iterator to show namespace nodes, which are modeled by DTM but not by the DOM.
static int	SHOW_NOTATION Show Notation nodes.
static int	SHOW_PROCESSING_INSTRUCTION Show ProcessingInstruction nodes.
static int	SHOW_TEXT Show Text nodes.

Method Summary

short	acceptNode(int nodeHandle, int whatToShow) Test whether a specified node is visible in the logical view of a DTMIterator.
short	acceptNode(int nodeHandle, int whatToShow, int expandedName) Test whether a specified node is visible in the logical view of a DTMIterator.

Field Detail

SHOW_ALL

public static final int SHOW_ALL

Show all Nodes.

SHOW_ELEMENT

public static final int SHOW_ELEMENT

Show Element nodes.

SHOW_ATTRIBUTE

public static final int SHOW_ATTRIBUTE

Show Attr nodes. This is meaningful only when creating an iterator or tree-walker 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 main document tree.

SHOW_TEXT

public static final int SHOW_TEXT

Show Text nodes.

SHOW_CDATA_SECTION

public static final int SHOW_CDATA_SECTION

Show CDATASection nodes.

SHOW_ENTITY_REFERENCE

public static final int SHOW_ENTITY_REFERENCE

Show EntityReference nodes. Note that if Entity References have been fully expanded while the tree was being constructed, these nodes will not appear and this mask has no effect.

SHOW_ENTITY

public static final int SHOW_ENTITY

Show Entity nodes. This is meaningful only when creating an iterator or tree-walker 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 main document tree.

SHOW_PROCESSING_INSTRUCTION

public static final int SHOW_PROCESSING_INSTRUCTION

Show ProcessingInstruction nodes.

SHOW_COMMENT

public static final int SHOW_COMMENT

Show Comment nodes.

SHOW_DOCUMENT

public static final int SHOW_DOCUMENT

Show Document nodes. (Of course, as with Attributes and such, this is meaningful only when the iteration root is the Document itself, since Document has no parent.)

SHOW_DOCUMENT_TYPE

public static final int SHOW_DOCUMENT_TYPE

Show DocumentType nodes.

SHOW_DOCUMENT_FRAGMENT

public static final int SHOW_DOCUMENT_FRAGMENT

Show DocumentFragment nodes. (Of course, as with Attributes and such, this is meaningful only when the iteration root is the Document itself, since DocumentFragment has no parent.)

SHOW_NOTATION

public static final int SHOW_NOTATION

Show Notation nodes. This is meaningful only when creating an iterator or tree-walker 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 main document tree.

SHOW_NAMESPACE

public static final int SHOW_NAMESPACE

This bit instructs the iterator to show namespace nodes, which are modeled by DTM but not by the DOM. Make sure this does not conflict with NodeFilter.

%REVIEW% Might be safer to start from higher bits and work down, to leave room for the DOM to expand its set of constants... Or, possibly, to create a DTM-specific field for these additional bits.

SHOW_BYFUNCTION

public static final int SHOW_BYFUNCTION

Special bit for filters implementing match patterns starting with a function. Make sure this does not conflict with NodeFilter.

%REVIEW% Might be safer to start from higher bits and work down, to leave room for the DOM to expand its set of constants... Or, possibly, to create a DTM-specific field for these additional bits.

Method Detail

acceptNode

public short acceptNode(int nodeHandle,
                        int whatToShow)

Test whether a specified node is visible in the logical view of a DTMIterator. Normally, this function will be called by the implementation of DTMIterator; it is not normally called directly from user code.

Parameters:

nodeHandle - int Handle of the node.

whatToShow - one of SHOW_XXX values.

Returns:

one of FILTER_ACCEPT, FILTER_REJECT, or FILTER_SKIP.

acceptNode

public short acceptNode(int nodeHandle,
                        int whatToShow,
                        int expandedName)

Test whether a specified node is visible in the logical view of a DTMIterator. Normally, this function will be called by the implementation of DTMIterator; it is not normally called directly from user code.

TODO: Should this be setNameMatch(expandedName) followed by accept()? Or will we really be testing a different name at every invocation?

%REVIEW% Under what circumstances will this be used? The cases I've considered are just as easy and just about as efficient if the name test is performed in the DTMIterator... -- Joe

%REVIEW% Should that 0xFFFF have a mnemonic assigned to it? Also: This representation is assuming the expanded name is indeed split into high/low 16-bit halfwords. If we ever change the balance between namespace and localname bits (eg because we decide there are many more localnames than namespaces, which is fairly likely), this is going to break. It might be safer to encapsulate the details with a makeExpandedName method and make that responsible for setting up the wildcard version as well.

Parameters:

nodeHandle - int Handle of the node.

whatToShow - one of SHOW_XXX values.

expandedName - a value defining the exanded name as defined in the DTM interface. Wild cards will be defined by 0xFFFF in the namespace and/or localname portion of the expandedName.

Returns:

one of FILTER_ACCEPT, FILTER_REJECT, or FILTER_SKIP.