org.apache.xerces.dom

Class DocumentImpl

java.lang.Object

org.apache.xerces.dom.NodeImpl

org.apache.xerces.dom.ChildNode

org.apache.xerces.dom.ParentNode

org.apache.xerces.dom.CoreDocumentImpl

org.apache.xerces.dom.DocumentImpl

All Implemented Interfaces:

Serializable, Cloneable, Document, DocumentEvent, EventTarget, Node, NodeList, org.w3c.dom.ranges.DocumentRange, org.w3c.dom.traversal.DocumentTraversal

Direct Known Subclasses:

DeferredDocumentImpl, HTMLDocumentImpl, PSVIDocumentImpl, WMLDocumentImpl

public class DocumentImpl
extends CoreDocumentImpl
implements org.w3c.dom.traversal.DocumentTraversal, DocumentEvent, org.w3c.dom.ranges.DocumentRange

The Document interface represents the entire HTML or XML document. Conceptually, it is the root of the document tree, and provides the primary access to the document's data.

Since elements, text nodes, comments, processing instructions, etc. cannot exist outside the context of a Document, the Document interface also contains the factory methods needed to create these objects. The Node objects created have a ownerDocument attribute which associates them with the Document within whose context they were created.

The DocumentImpl class also implements the DOM Level 2 DocumentTraversal interface. This interface is comprised of factory methods needed to create NodeIterators and TreeWalkers. The process of creating NodeIterator objects also adds these references to this document. After finishing with an iterator it is important to remove the object using the remove methods in this implementation. This allows the release of the references from the iterator objects to the DOM Nodes.

Note: When any node in the document is serialized, the entire document is serialized along with it.

Since:

PR-DOM-Level-1-19980818.

Version:

$Id$

Author:

Arnaud Le Hors, IBM, Joe Kesselman, IBM, Andy Clark, IBM, Ralf Pfeiffer, IBM

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Hashtable	eventListeners Table for event listeners registered to this document nodes.
protected ReferenceQueue	iteratorReferenceQueue Reference queue for cleared Node Iterator references
protected List	iterators Node Iterators
protected boolean	mutationEvents Bypass mutation events firing.
protected ReferenceQueue	rangeReferenceQueue Reference queue for cleared Range references
protected List	ranges Ranges

Fields inherited from class org.apache.xerces.dom.CoreDocumentImpl

actualEncoding, allowGrammarAccess, changes, docElement, docType, encoding, errorChecking, fDocumentURI, identifiers, standalone, userData, version, xmlVersionChanged

Fields inherited from class org.apache.xerces.dom.ParentNode

firstChild, fNodeListCache, ownerDocument

Fields inherited from class org.apache.xerces.dom.ChildNode

nextSibling, previousSibling

Fields inherited from class org.apache.xerces.dom.NodeImpl

DOCUMENT_POSITION_CONTAINS, DOCUMENT_POSITION_DISCONNECTED, DOCUMENT_POSITION_FOLLOWING, DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC, DOCUMENT_POSITION_IS_CONTAINED, DOCUMENT_POSITION_PRECEDING, ELEMENT_DEFINITION_NODE, FIRSTCHILD, flags, HASSTRING, ID, IGNORABLEWS, NORMALIZED, OWNED, ownerNode, READONLY, SPECIFIED, SYNCCHILDREN, SYNCDATA, TREE_POSITION_ANCESTOR, TREE_POSITION_DESCENDANT, TREE_POSITION_DISCONNECTED, TREE_POSITION_EQUIVALENT, TREE_POSITION_FOLLOWING, TREE_POSITION_PRECEDING, TREE_POSITION_SAME_NODE

Fields inherited from interface org.w3c.dom.Node

ATTRIBUTE_NODE, CDATA_SECTION_NODE, COMMENT_NODE, DOCUMENT_FRAGMENT_NODE, DOCUMENT_NODE, DOCUMENT_POSITION_CONTAINED_BY, DOCUMENT_POSITION_CONTAINS, DOCUMENT_POSITION_DISCONNECTED, DOCUMENT_POSITION_FOLLOWING, DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC, DOCUMENT_POSITION_PRECEDING, DOCUMENT_TYPE_NODE, ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, NOTATION_NODE, PROCESSING_INSTRUCTION_NODE, TEXT_NODE

Constructor Summary

Constructors

Constructor and Description
DocumentImpl() NON-DOM: Actually creating a Document is outside the DOM's spec, since it has to operate in terms of a particular implementation.
DocumentImpl(boolean grammarAccess) Constructor.
DocumentImpl(DocumentType doctype) For DOM2 support.
DocumentImpl(DocumentType doctype, boolean grammarAccess) For DOM2 support.

Method Summary

Modifier and Type	Method and Description
protected void	addEventListener(NodeImpl node, String type, EventListener listener, boolean useCapture) Introduced in DOM Level 2.
Node	cloneNode(boolean deep) Deep-clone a document, including fixing ownerDoc for the cloned children.
protected void	copyEventListeners(NodeImpl src, NodeImpl tgt)
Event	createEvent(String type) Introduced in DOM Level 2.
org.w3c.dom.traversal.NodeIterator	createNodeIterator(Node root, int whatToShow, org.w3c.dom.traversal.NodeFilter filter, boolean entityReferenceExpansion) Create and return a NodeIterator.
org.w3c.dom.traversal.NodeIterator	createNodeIterator(Node root, short whatToShow, org.w3c.dom.traversal.NodeFilter filter) NON-DOM extension: Create and return a NodeIterator.
org.w3c.dom.ranges.Range	createRange()
org.w3c.dom.traversal.TreeWalker	createTreeWalker(Node root, int whatToShow, org.w3c.dom.traversal.NodeFilter filter, boolean entityReferenceExpansion) Create and return a TreeWalker.
org.w3c.dom.traversal.TreeWalker	createTreeWalker(Node root, short whatToShow, org.w3c.dom.traversal.NodeFilter filter) NON-DOM extension: Create and return a TreeWalker.
protected void	dispatchAggregateEvents(NodeImpl node, AttrImpl enclosingAttr, String oldvalue, short change) NON-DOM INTERNAL: Generate the "aggregated" post-mutation events DOMAttrModified and DOMSubtreeModified.
protected void	dispatchAggregateEvents(NodeImpl node, org.apache.xerces.dom.DocumentImpl.EnclosingAttr ea) NON-DOM INTERNAL: Convenience wrapper for calling dispatchAggregateEvents when the context was established by savedEnclosingAttr.
protected boolean	dispatchEvent(NodeImpl node, Event event) Introduced in DOM Level 2.
protected void	dispatchEventToSubtree(Node n, Event e) NON-DOM INTERNAL: DOMNodeInsertedIntoDocument and ...RemovedFrom...
protected void	dispatchingEventToSubtree(Node n, Event e) Dispatches event to the target node's descendents recursively
protected Vector	getEventListeners(NodeImpl n) Retreive event listener registered on a given node
DOMImplementation	getImplementation() Retrieve information describing the abilities of this particular DOM implementation.
protected void	removeEventListener(NodeImpl node, String type, EventListener listener, boolean useCapture) Introduced in DOM Level 2.
protected void	saveEnclosingAttr(NodeImpl node) NON-DOM INTERNAL: Pre-mutation context check, in preparation for later generating DOMAttrModified events.
protected void	setEventListeners(NodeImpl n, Vector listeners) Store event listener registered on a given node This is another place where we could use weak references! Indeed, the node here won't be GC'ed as long as some listener is registered on it, since the eventsListeners table will have a reference to the node.

Methods inherited from class org.apache.xerces.dom.CoreDocumentImpl

abort, adoptNode, callUserDataHandlers, canRenameElements, changed, changes, checkDOMNSErr, checkNamespaceWF, checkQName, clearIdentifiers, clone, cloneNode, createAttribute, createAttributeNS, createAttributeNS, createCDATASection, createComment, createDocumentFragment, createDocumentType, createElement, createElementDefinition, createElementNS, createElementNS, createEntity, createEntityReference, createNotation, createProcessingInstruction, createTextNode, getAsync, getBaseURI, getDoctype, getDocumentElement, getDocumentURI, getDomConfig, getElementById, getElementsByTagName, getElementsByTagNameNS, getEncoding, getErrorChecking, getFeature, getIdentifier, getIdentifiers, getInputEncoding, getNodeName, getNodeNumber, getNodeNumber, getNodeType, getOwnerDocument, getStandalone, getStrictErrorChecking, getTextContent, getUserData, getUserData, getUserDataRecord, getVersion, getXmlEncoding, getXmlStandalone, getXmlVersion, importNode, insertBefore, isKidOK, isValidQName, isXMLName, load, loadXML, normalizeDocument, putIdentifier, removeChild, removeIdentifier, renameNode, replaceChild, saveXML, setAsync, setDocumentURI, setEncoding, setErrorChecking, setInputEncoding, setStandalone, setStrictErrorChecking, setTextContent, setUserData, setUserData, setVersion, setXmlEncoding, setXmlStandalone, setXmlVersion, undeferChildren

Methods inherited from class org.apache.xerces.dom.ParentNode

getChildNodes, getChildNodesUnoptimized, getFirstChild, getLastChild, getLength, hasChildNodes, isEqualNode, item, normalize, setOwnerDocument, setReadOnly, synchronizeChildren

Methods inherited from class org.apache.xerces.dom.ChildNode

getNextSibling, getParentNode, getPreviousSibling

Methods inherited from class org.apache.xerces.dom.NodeImpl

addEventListener, appendChild, compareDocumentPosition, compareTreePosition, dispatchEvent, getAttributes, getContainer, getLocalName, getNamespaceURI, getNodeValue, getPrefix, getReadOnly, getUserData, getUserData, getUserDataRecord, hasAttributes, isDefaultNamespace, isSameNode, isSupported, lookupNamespaceURI, lookupPrefix, needsSyncChildren, removeEventListener, setNodeValue, setPrefix, setUserData, setUserData, synchronizeData, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.w3c.dom.Node

appendChild, compareDocumentPosition, getAttributes, getChildNodes, getFirstChild, getLastChild, getLocalName, getNamespaceURI, getNextSibling, getNodeValue, getParentNode, getPrefix, getPreviousSibling, getUserData, hasAttributes, hasChildNodes, isDefaultNamespace, isEqualNode, isSameNode, isSupported, lookupNamespaceURI, lookupPrefix, normalize, setNodeValue, setPrefix, setUserData

Field Detail

iterators

protected transient List iterators

Node Iterators

iteratorReferenceQueue

protected transient ReferenceQueue iteratorReferenceQueue

Reference queue for cleared Node Iterator references

ranges

protected transient List ranges

Ranges

rangeReferenceQueue

protected transient ReferenceQueue rangeReferenceQueue

Reference queue for cleared Range references

eventListeners

protected Hashtable eventListeners

Table for event listeners registered to this document nodes.

mutationEvents

protected boolean mutationEvents

Bypass mutation events firing.

Constructor Detail

DocumentImpl

public DocumentImpl()

NON-DOM: Actually creating a Document is outside the DOM's spec, since it has to operate in terms of a particular implementation.

DocumentImpl

public DocumentImpl(boolean grammarAccess)

Constructor.

DocumentImpl

public DocumentImpl(DocumentType doctype)

For DOM2 support. The createDocument factory method is in DOMImplementation.

DocumentImpl

public DocumentImpl(DocumentType doctype,
                    boolean grammarAccess)

For DOM2 support.

Method Detail

cloneNode

public Node cloneNode(boolean deep)

Deep-clone a document, including fixing ownerDoc for the cloned children. Note that this requires bypassing the WRONG_DOCUMENT_ERR protection. I've chosen to implement it by calling importNode which is DOM Level 2.

Specified by:

cloneNode in interface Node

Overrides:

cloneNode in class CoreDocumentImpl

Parameters:

deep - boolean, iff true replicate children

Returns:

org.w3c.dom.Node

See Also:

Example: Cloning a Text node will copy both the node and the text it contains.

Example: Cloning something that has children -- Element or Attr, for example -- will _not_ clone those children unless a "deep clone" has been requested. A shallow clone of an Attr node will yield an empty Attr of the same name.

NOTE: Clones will always be read/write, even if the node being cloned is read-only, to permit applications using only the DOM API to obtain editable copies of locked portions of the tree.

getImplementation

public DOMImplementation getImplementation()

Retrieve information describing the abilities of this particular DOM implementation. Intended to support applications that may be using DOMs retrieved from several different sources, potentially with different underlying representations.

Specified by:

getImplementation in interface Document

Overrides:

getImplementation in class CoreDocumentImpl

createNodeIterator

public org.w3c.dom.traversal.NodeIterator createNodeIterator(Node root,
                                                             short whatToShow,
                                                             org.w3c.dom.traversal.NodeFilter filter)

NON-DOM extension: Create and return a NodeIterator. The NodeIterator is added to a list of NodeIterators so that it can be removed to free up the DOM Nodes it references.

Parameters:

root - The root of the iterator.

whatToShow - The whatToShow mask.

filter - The NodeFilter installed. Null means no filter.

createNodeIterator

public org.w3c.dom.traversal.NodeIterator createNodeIterator(Node root,
                                                             int whatToShow,
                                                             org.w3c.dom.traversal.NodeFilter filter,
                                                             boolean entityReferenceExpansion)

Create and return a NodeIterator. The NodeIterator is added to a list of NodeIterators so that it can be removed to free up the DOM Nodes it references.

Specified by:

createNodeIterator in interface org.w3c.dom.traversal.DocumentTraversal

Parameters:

root - The root of the iterator.

whatToShow - The whatToShow mask.

filter - The NodeFilter installed. Null means no filter.

entityReferenceExpansion - true to expand the contents of EntityReference nodes

Since:

WD-DOM-Level-2-19990923

createTreeWalker

public org.w3c.dom.traversal.TreeWalker createTreeWalker(Node root,
                                                         short whatToShow,
                                                         org.w3c.dom.traversal.NodeFilter filter)

NON-DOM extension: Create and return a TreeWalker.

Parameters:

root - The root of the iterator.

whatToShow - The whatToShow mask.

filter - The NodeFilter installed. Null means no filter.

createTreeWalker

public org.w3c.dom.traversal.TreeWalker createTreeWalker(Node root,
                                                         int whatToShow,
                                                         org.w3c.dom.traversal.NodeFilter filter,
                                                         boolean entityReferenceExpansion)

Create and return a TreeWalker.

Specified by:

createTreeWalker in interface org.w3c.dom.traversal.DocumentTraversal

Parameters:

root - The root of the iterator.

whatToShow - The whatToShow mask.

filter - The NodeFilter installed. Null means no filter.

entityReferenceExpansion - true to expand the contents of EntityReference nodes

Since:

WD-DOM-Level-2-19990923

createRange

public org.w3c.dom.ranges.Range createRange()

Specified by:

createRange in interface org.w3c.dom.ranges.DocumentRange

createEvent

public Event createEvent(String type)
                  throws DOMException

Introduced in DOM Level 2. Optional.

Create and return Event objects.

Specified by:

createEvent in interface DocumentEvent

Parameters:

type - The eventType parameter specifies the type of Event interface to be created. If the Event interface specified is supported by the implementation this method will return a new Event of the interface type requested. If the Event is to be dispatched via the dispatchEvent method the appropriate event init method must be called after creation in order to initialize the Event's values. As an example, a user wishing to synthesize some kind of Event would call createEvent with the parameter "Events". The initEvent method could then be called on the newly created Event to set the specific type of Event to be dispatched and set its context information.

Returns:

Newly created Event

Throws:

DOMException - NOT_SUPPORTED_ERR: Raised if the implementation does not support the type of Event interface requested

Since:

WD-DOM-Level-2-19990923

setEventListeners

protected void setEventListeners(NodeImpl n,
                                 Vector listeners)

Store event listener registered on a given node This is another place where we could use weak references! Indeed, the node here won't be GC'ed as long as some listener is registered on it, since the eventsListeners table will have a reference to the node.

getEventListeners

protected Vector getEventListeners(NodeImpl n)

Retreive event listener registered on a given node

addEventListener

protected void addEventListener(NodeImpl node,
                                String type,
                                EventListener listener,
                                boolean useCapture)

Introduced in DOM Level 2.

Register an event listener with this Node. A listener may be independently registered as both Capturing and Bubbling, but may only be registered once per role; redundant registrations are ignored.

Overrides:

addEventListener in class CoreDocumentImpl

Parameters:

node - node to add listener to

type - Event name (NOT event group!) to listen for.

listener - Who gets called when event is dispatched

useCapture - True iff listener is registered on capturing phase rather than at-target or bubbling

removeEventListener

protected void removeEventListener(NodeImpl node,
                                   String type,
                                   EventListener listener,
                                   boolean useCapture)

Introduced in DOM Level 2.

Deregister an event listener previously registered with this Node. A listener must be independently removed from the Capturing and Bubbling roles. Redundant removals (of listeners not currently registered for this role) are ignored.

Overrides:

removeEventListener in class CoreDocumentImpl

Parameters:

node - node to remove listener from

type - Event name (NOT event group!) to listen for.

listener - Who gets called when event is dispatched

useCapture - True iff listener is registered on capturing phase rather than at-target or bubbling

copyEventListeners

protected void copyEventListeners(NodeImpl src,
                                  NodeImpl tgt)

Overrides:

copyEventListeners in class CoreDocumentImpl

dispatchEvent

protected boolean dispatchEvent(NodeImpl node,
                                Event event)

Introduced in DOM Level 2.

Distribution engine for DOM Level 2 Events.

Event propagation runs as follows:

1. Event is dispatched to a particular target node, which invokes this code. Note that the event's stopPropagation flag is cleared when dispatch begins; thereafter, if it has been set before processing of a node commences, we instead immediately advance to the DEFAULT phase.
2. The node's ancestors are established as destinations for events. For capture and bubble purposes, node ancestry is determined at the time dispatch starts. If an event handler alters the document tree, that does not change which nodes will be informed of the event.
3. CAPTURING_PHASE: Ancestors are scanned, root to target, for Capturing listeners. If found, they are invoked (see below).
4. AT_TARGET: Event is dispatched to NON-CAPTURING listeners on the target node. Note that capturing listeners on this node are _not_ invoked.
5. BUBBLING_PHASE: Ancestors are scanned, target to root, for non-capturing listeners.
6. Default processing: Some DOMs have default behaviors bound to specific nodes. If this DOM does, and if the event's preventDefault flag has not been set, we now return to the target node and process its default handler for this event, if any.

Note that registration of handlers during processing of an event does not take effect during this phase of this event; they will not be called until the next time this node is visited by dispatchEvent. On the other hand, removals take effect immediately.

If an event handler itself causes events to be dispatched, they are processed synchronously, before processing resumes on the event which triggered them. Please be aware that this may result in events arriving at listeners "out of order" relative to the actual sequence of requests.

Note that our implementation resets the event's stop/prevent flags when dispatch begins. I believe the DOM's intent is that event objects be redispatchable, though it isn't stated in those terms.

Overrides:

dispatchEvent in class CoreDocumentImpl

Parameters:

node - node to dispatch to

event - the event object to be dispatched to registered EventListeners

Returns:

true if the event's preventDefault() method was invoked by an EventListener; otherwise false.

dispatchEventToSubtree

protected void dispatchEventToSubtree(Node n,
                                      Event e)

NON-DOM INTERNAL: DOMNodeInsertedIntoDocument and ...RemovedFrom... are dispatched to an entire subtree. This is the distribution code therefor. They DO NOT bubble, thanks be, but may be captured.

Similar to code in dispatchingEventToSubtree however this method is only used on the target node and does not start a dispatching chain on the sibling of the target node as this is not part of the subtree ***** At the moment I'm being sloppy and using the normal capture dispatcher on every node. This could be optimized hugely by writing a capture engine that tracks our position in the tree to update the capture chain without repeated chases up to root.

Parameters:

n - target node (that was directly inserted or removed)

e - event to be sent to that node and its subtree

dispatchingEventToSubtree

protected void dispatchingEventToSubtree(Node n,
                                         Event e)

Dispatches event to the target node's descendents recursively

Parameters:

n - node to dispatch to

e - event to be sent to that node and its subtree

dispatchAggregateEvents

protected void dispatchAggregateEvents(NodeImpl node,
                                       org.apache.xerces.dom.DocumentImpl.EnclosingAttr ea)

NON-DOM INTERNAL: Convenience wrapper for calling dispatchAggregateEvents when the context was established by savedEnclosingAttr.

Parameters:

node - node to dispatch to

ea - description of Attr affected by current operation

dispatchAggregateEvents

protected void dispatchAggregateEvents(NodeImpl node,
                                       AttrImpl enclosingAttr,
                                       String oldvalue,
                                       short change)

NON-DOM INTERNAL: Generate the "aggregated" post-mutation events DOMAttrModified and DOMSubtreeModified. Both of these should be issued only once for each user-requested mutation operation, even if that involves multiple changes to the DOM. For example, if a DOM operation makes multiple changes to a single Attr before returning, it would be nice to generate only one DOMAttrModified, and multiple changes over larger scope but within a recognizable single subtree might want to generate only one DOMSubtreeModified, sent to their lowest common ancestor.

To manage this, use the "internal" versions of insert and remove with MUTATION_LOCAL, then make an explicit call to this routine at the higher level. Some examples now exist in our code.

Parameters:

node - The node to dispatch to

enclosingAttr - The Attr node (if any) whose value has been changed as a result of the DOM operation. Null if none such.

oldvalue - The String value previously held by the enclosingAttr. Ignored if none such.

change - Type of modification to the attr. See MutationEvent.attrChange

saveEnclosingAttr

protected void saveEnclosingAttr(NodeImpl node)

NON-DOM INTERNAL: Pre-mutation context check, in preparation for later generating DOMAttrModified events. Determines whether this node is within an Attr

Parameters:

node - node to get enclosing attribute for