org.htmlunit.xpath.xml.dtm.ref.dom2dtm

Class DOM2DTM

java.lang.Object

org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBase

org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBaseTraversers

org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBaseIterators

org.htmlunit.xpath.xml.dtm.ref.dom2dtm.DOM2DTM

All Implemented Interfaces:

DTM

public class DOM2DTM
extends DTMDefaultBaseIterators

The DOM2DTM class serves up a DOM's contents via the DTM API.

Note that it doesn't necessarily represent a full Document tree. You can wrap a DOM2DTM around a specific node and its subtree and the right things should happen. (I don't _think_ we currently support DocumentFrgment nodes as roots, though that might be worth considering.)

Note too that we do not currently attempt to track document mutation. If you alter the DOM after wrapping DOM2DTM around it, all bets are off.

Nested Class Summary

Nested classes/interfaces inherited from class org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBaseIterators

DTMDefaultBaseIterators.AncestorIterator, DTMDefaultBaseIterators.AttributeIterator, DTMDefaultBaseIterators.ChildrenIterator, DTMDefaultBaseIterators.DescendantIterator, DTMDefaultBaseIterators.FollowingIterator, DTMDefaultBaseIterators.FollowingSiblingIterator, DTMDefaultBaseIterators.InternalAxisIteratorBase, DTMDefaultBaseIterators.NamespaceIterator, DTMDefaultBaseIterators.ParentIterator, DTMDefaultBaseIterators.PrecedingIterator, DTMDefaultBaseIterators.PrecedingSiblingIterator, DTMDefaultBaseIterators.RootIterator, DTMDefaultBaseIterators.SingletonIterator

Field Summary

Fields

Modifier and Type	Field and Description
protected Vector<Node>	m_nodes The node objects.

Fields inherited from class org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBase

DEFAULT_BLOCKSIZE, DEFAULT_NUMBLOCKS, DEFAULT_NUMBLOCKS_SMALL, m_documentBaseURI, m_dtmIdent, m_elemIndexes, m_expandedNameTable, m_exptype, m_firstch, m_indexing, m_mgr, m_mgrDefault, m_namespaceDeclSetElements, m_namespaceDeclSets, m_nextsib, m_parent, m_prevsib, m_size, m_traversers, NOTPROCESSED, ROOTNODE

Fields inherited from interface org.htmlunit.xpath.xml.dtm.DTM

ATTRIBUTE_NODE, CDATA_SECTION_NODE, COMMENT_NODE, DOCUMENT_FRAGMENT_NODE, DOCUMENT_NODE, DOCUMENT_TYPE_NODE, ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, NAMESPACE_NODE, NOTATION_NODE, NTYPES, NULL, PROCESSING_INSTRUCTION_NODE, TEXT_NODE

Constructor Summary

Constructors

Constructor and Description
DOM2DTM(DTMManager mgr, DOMSource domSource, int dtmIdentity, boolean doIndexing) Construct a DOM2DTM object from a DOM node.

Method Summary

Modifier and Type	Method and Description
protected int	addNode(Node node, int parentIndex, int previousSibling, int forceNodeType) Construct the node map from the node.
int	getAttributeNode(int nodeHandle, String namespaceURI, String name) Retrieves an attribute node by local name and namespace URI
int	getElementById(String elementId) Returns the Element whose ID is given by elementId.
int	getHandleOfNode(Node node) Get the handle from a Node.
String	getLocalName(int nodeHandle) Given a node handle, return its DOM-style localname.
String	getNamespaceURI(int nodeHandle) Given a node handle, return its DOM-style namespace URI (As defined in Namespaces, this is the declared URI which this node's prefix -- or default in lieu thereof -- was mapped to.)
protected int	getNextNodeIdentity(int identity) Get the next node identity value in the list, and call the iterator if it hasn't been added yet.
Node	getNode(int nodeHandle) Return an DOM node for the given node.
protected static void	getNodeData(Node node, StringBuilder buf) Retrieve the text content of a DOM subtree, appending it into a user-supplied FastStringBuffer object.
String	getNodeName(int nodeHandle) Given a node handle, return its DOM-style node name.
String	getNodeNameX(int nodeHandle) Given a node handle, return the XPath node name.
String	getNodeValue(int nodeHandle) Given a node handle, return its node value.
String	getPrefix(int nodeHandle) Given a namespace handle, return the prefix that the namespace decl is mapping.
XString	getStringValue(int nodeHandle) Get the string-value of a node as a String object (see ... for the definition of a node's string-value).
protected Node	lookupNode(int nodeIdentity) Get a Node from an identity index.
protected boolean	nextNode() This method should try and build one or more nodes in the table.

Methods inherited from class org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBaseIterators

getAxisIterator

Methods inherited from class org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBaseTraversers

getAxisTraverser

Methods inherited from class org.htmlunit.xpath.xml.dtm.ref.DTMDefaultBase

_exptype, _firstch, _level, _nextsib, _parent, _prevsib, _type, declareNamespaceInContext, dumpDTM, dumpNode, ensureSizeOfIndex, findGTE, findInSortedSuballocatedIntVector, findNamespaceContext, getDocument, getDocumentRoot, getExpandedTypeID, getExpandedTypeID, getFirstAttribute, getFirstAttributeIdentity, getFirstChild, getFirstNamespaceNode, getLastChild, getManager, getNextAttribute, getNextAttributeIdentity, getNextNamespaceNode, getNextSibling, getNodeType, getOwnerDocument, getParent, getPreviousSibling, indexNode, isNodeAfter, makeNodeHandle, makeNodeIdentity

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_nodes

protected final Vector<Node> m_nodes

The node objects. The instance part of the handle indexes directly into this vector. Each DTM node may actually be composed of several DOM nodes (for example, if logically-adjacent Text/CDATASection nodes in the DOM have been coalesced into a single DTM Text node); this table points only to the first in that sequence.

Constructor Detail

DOM2DTM

public DOM2DTM(DTMManager mgr,
               DOMSource domSource,
               int dtmIdentity,
               boolean doIndexing)

Construct a DOM2DTM object from a DOM node.

Parameters:

mgr - The DTMManager who owns this DTM.

domSource - the DOM source that this DTM will wrap.

dtmIdentity - The DTM identity ID for this DTM.

doIndexing - true if the caller considers it worth it to use indexing schemes.

Method Detail

addNode

protected int addNode(Node node,
                      int parentIndex,
                      int previousSibling,
                      int forceNodeType)

Construct the node map from the node.

Parameters:

node - The node that is to be added to the DTM.

parentIndex - The current parent index.

previousSibling - The previous sibling index.

forceNodeType - If not DTM.NULL, overrides the DOM node type. Used to force nodes to Text rather than CDATASection when their coalesced value includes ordinary Text nodes (current DTM behavior).

Returns:

The index identity of the node that was added.

nextNode

protected boolean nextNode()

This method should try and build one or more nodes in the table.

Specified by:

nextNode in class DTMDefaultBase

Returns:

The true if a next node is found or false if there are no more nodes.

getNode

public Node getNode(int nodeHandle)

Return an DOM node for the given node.

Specified by:

getNode in interface DTM

Overrides:

getNode in class DTMDefaultBase

Parameters:

nodeHandle - The node ID.

Returns:

A node representation of the DTM node.

lookupNode

protected Node lookupNode(int nodeIdentity)

Get a Node from an identity index.

NEEDSDOC @param nodeIdentity

NEEDSDOC ($objectName$) @return

getNextNodeIdentity

protected int getNextNodeIdentity(int identity)

Get the next node identity value in the list, and call the iterator if it hasn't been added yet.

Specified by:

getNextNodeIdentity in class DTMDefaultBase

Parameters:

identity - The node identity (index).

Returns:

identity+1, or DTM.NULL.

getHandleOfNode

public int getHandleOfNode(Node node)

Get the handle from a Node. This is a more robust version of getHandleFromNode, intended to be usable by the public.

%OPT% This will be pretty slow. %REVIEW% This relies on being able to test node-identity via object-identity. DTM2DOM proxying is a great example of a case where that doesn't work. DOM Level 3 will provide the isSameNode() method to fix that, but until then this is going to be flaky.

Parameters:

node - A node, which may be null.

Returns:

The node handle or DTM.NULL.

getAttributeNode

public int getAttributeNode(int nodeHandle,
                            String namespaceURI,
                            String name)

Retrieves an attribute node by local name and namespace URI

%TBD% Note that we currently have no way to support the DOM's old getAttribute() call, which accesses only the qname.

Specified by:

getAttributeNode in interface DTM

Specified by:

getAttributeNode in class DTMDefaultBase

Parameters:

nodeHandle - Handle of the node upon which to look up this attribute.

namespaceURI - The namespace URI of the attribute to retrieve, or null.

name - The local name of the attribute to retrieve.

Returns:

The attribute node handle with the specified name ( nodeName) or DTM.NULL if there is no such attribute.

getStringValue

public XString getStringValue(int nodeHandle)

Get the string-value of a node as a String object (see ... for the definition of a node's string-value).

Specified by:

getStringValue in interface DTM

Specified by:

getStringValue in class DTMDefaultBase

Parameters:

nodeHandle - The node ID.

Returns:

A string object that represents the string-value of the given node.

getNodeData

protected static void getNodeData(Node node,
                                  StringBuilder buf)

Retrieve the text content of a DOM subtree, appending it into a user-supplied FastStringBuffer object. Note that attributes are not considered part of the content of an element.

There are open questions regarding whitespace stripping. Currently we make no special effort in that regard, since the standard DOM doesn't yet provide DTD-based information to distinguish whitespace-in-element-context from genuine #PCDATA. Note that we should probably also consider xml:space if/when we address this. DOM Level 3 may solve the problem for us.

%REVIEW% Actually, since this method operates on the DOM side of the fence rather than the DTM side, it SHOULDN'T do any special handling. The DOM does what the DOM does; if you want DTM-level abstractions, use DTM-level methods.

Parameters:

node - Node whose subtree is to be walked, gathering the contents of all Text or CDATASection nodes.

buf - StringBuilder into which the contents of the text nodes are to be concatenated.

getNodeName

public String getNodeName(int nodeHandle)

Given a node handle, return its DOM-style node name. This will include names such as #text or #document.

Specified by:

getNodeName in interface DTM

Specified by:

getNodeName in class DTMDefaultBase

Parameters:

nodeHandle - the id of the node.

Returns:

String Name of this node, which may be an empty string. %REVIEW% Document when empty string is possible...

getNodeNameX

public String getNodeNameX(int nodeHandle)

Given a node handle, return the XPath node name. This should be the name as described by the XPath data model, NOT the DOM-style name.

Specified by:

getNodeNameX in interface DTM

Overrides:

getNodeNameX in class DTMDefaultBase

Parameters:

nodeHandle - the id of the node.

Returns:

String Name of this node.

getLocalName

public String getLocalName(int nodeHandle)

Given a node handle, return its DOM-style localname. (As defined in Namespaces, this is the portion of the name after the prefix, if present, or the whole node name if no prefix exists)

Specified by:

getLocalName in interface DTM

Specified by:

getLocalName in class DTMDefaultBase

Parameters:

nodeHandle - the id of the node.

Returns:

String Local name of this node.

getPrefix

public String getPrefix(int nodeHandle)

Given a namespace handle, return the prefix that the namespace decl is mapping. Given a node handle, return the prefix used to map to the namespace. (As defined in Namespaces, this is the portion of the name before any colon character).

%REVIEW% Are you sure you want "" for no prefix?

Specified by:

getPrefix in interface DTM

Specified by:

getPrefix in class DTMDefaultBase

Parameters:

nodeHandle - the id of the node.

Returns:

String prefix of this node's name, or "" if no explicit namespace prefix was given.

getNamespaceURI

public String getNamespaceURI(int nodeHandle)

Given a node handle, return its DOM-style namespace URI (As defined in Namespaces, this is the declared URI which this node's prefix -- or default in lieu thereof -- was mapped to.)

Specified by:

getNamespaceURI in interface DTM

Specified by:

getNamespaceURI in class DTMDefaultBase

Parameters:

nodeHandle - the id of the node.

Returns:

String URI value of this node's namespace, or null if no namespace was resolved.

getNodeValue

public String getNodeValue(int nodeHandle)

Given a node handle, return its node value. This is mostly as defined by the DOM, but may ignore some conveniences.

Specified by:

getNodeValue in interface DTM

Specified by:

getNodeValue in class DTMDefaultBase

Parameters:

nodeHandle - The node id.

Returns:

String Value of this node, or null if not meaningful for this node type.

getElementById

public int getElementById(String elementId)

Returns the Element whose ID is given by elementId. If no such element exists, returns DTM.NULL. Behavior is not defined if more than one element has this ID. Attributes (including those with the name "ID") are not of type ID unless so defined by DTD/Schema information available to the DTM implementation. Implementations that do not know whether attributes are of type ID or not are expected to return DTM.NULL.

%REVIEW% Presumably IDs are still scoped to a single document, and this operation searches only within a single document, right? Wouldn't want collisions between DTMs in the same process.

Specified by:

getElementById in interface DTM

Specified by:

getElementById in class DTMDefaultBase

Parameters:

elementId - The unique id value for an element.

Returns:

The handle of the matching element.