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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.xerces.dom;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import org.w3c.dom.Attr;
import org.w3c.dom.DOMException;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.w3c.dom.TypeInfo;
/**
* Attribute represents an XML-style attribute of an
* Element. Typically, the allowable values are controlled by its
* declaration in the Document Type Definition (DTD) governing this
* kind of document.
*
* If the attribute has not been explicitly assigned a value, but has
* been declared in the DTD, it will exist and have that default. Only
* if neither the document nor the DTD specifies a value will the
* Attribute really be considered absent and have no value; in that
* case, querying the attribute will return null.
*
* Attributes may have multiple children that contain their data. (XML
* allows attributes to contain entity references, and tokenized
* attribute types such as NMTOKENS may have a child for each token.)
* For convenience, the Attribute object's getValue() method returns
* the string version of the attribute's value.
*
* Attributes are not children of the Elements they belong to, in the
* usual sense, and have no valid Parent reference. However, the spec
* says they _do_ belong to a specific Element, and an INUSE exception
* is to be thrown if the user attempts to explicitly share them
* between elements.
*
* Note that Elements do not permit attributes to appear to be shared
* (see the INUSE exception), so this object's mutability is
* officially not an issue.
*
* Note: The ownerNode attribute is used to store the Element the Attr
* node is associated with. Attr nodes do not have parent nodes.
* Besides, the getOwnerElement() method can be used to get the element node
* this attribute is associated with.
*
* AttrImpl does not support Namespaces. AttrNSImpl, which inherits from
* it, does.
*
*
AttrImpl used to inherit from ParentNode. It now directly inherits from
* NodeImpl and provide its own implementation of the ParentNode's behavior.
* The reason is that we now try and avoid to always create a Text node to
* hold the value of an attribute. The DOM spec requires it, so we still have
* to do it in case getFirstChild() is called for instance. The reason
* attribute values are stored as a list of nodes is so that they can carry
* more than a simple string. They can also contain EntityReference nodes.
* However, most of the times people only have a single string that they only
* set and get through Element.set/getAttribute or Attr.set/getValue. In this
* new version, the Attr node has a value pointer which can either be the
* String directly or a pointer to the first ChildNode. A flag tells which one
* it currently is. Note that while we try to stick with the direct String as
* much as possible once we've switched to a node there is no going back. This
* is because we have no way to know whether the application keeps referring to
* the node we once returned.
*
The gain in memory varies on the density of attributes in the document.
* But in the tests I've run I've seen up to 12% of memory gain. And the good
* thing is that it also leads to a slight gain in speed because we allocate
* fewer objects! I mean, that's until we have to actually create the node...
*
* To avoid too much duplicated code, I got rid of ParentNode and renamed
* ChildAndParentNode, which I never really liked, to ParentNode for
* simplicity, this doesn't make much of a difference in memory usage because
* there are only very few objects that are only a Parent. This is only true
* now because AttrImpl now inherits directly from NodeImpl and has its own
* implementation of the ParentNode's node behavior. So there is still some
* duplicated code there.
*
* This class doesn't directly support mutation events, however, it notifies
* the document when mutations are performed so that the document class do so.
*
*
WARNING: Some of the code here is partially duplicated in
* ParentNode, be careful to keep these two classes in sync!
*
* @xerces.internal
*
* @see AttrNSImpl
*
* @author Arnaud Le Hors, IBM
* @author Joe Kesselman, IBM
* @author Andy Clark, IBM
* @version $Id: AttrImpl.java 924245 2010-03-17 11:58:14Z mrglavas $
* @since PR-DOM-Level-1-19980818.
*
*/
public class AttrImpl
extends NodeImpl
implements Attr, TypeInfo{
//
// Constants
//
/** Serialization version. */
static final long serialVersionUID = 7277707688218972102L;
/** DTD namespace. **/
static final String DTD_URI = "http://www.w3.org/TR/REC-xml";
//
// Data
//
/** This can either be a String or the first child node. */
protected Object value = null;
/** Attribute name. */
protected String name;
/** Type information */
// REVISIT: we are losing the type information in DOM during serialization
transient Object type;
//
// Constructors
//
/**
* Attribute has no public constructor. Please use the factory
* method in the Document class.
*/
protected AttrImpl(CoreDocumentImpl ownerDocument, String name) {
super(ownerDocument);
this.name = name;
/** False for default attributes. */
isSpecified(true);
hasStringValue(true);
}
// for AttrNSImpl
protected AttrImpl() {}
// Support for DOM Level 3 renameNode method.
// Note: This only deals with part of the pb. It is expected to be
// called after the Attr has been detached for one thing.
// CoreDocumentImpl does all the work.
void rename(String name) {
if (needsSyncData()) {
synchronizeData();
}
this.name = name;
}
// create a real text node as child if we don't have one yet
protected void makeChildNode() {
if (hasStringValue()) {
if (value != null) {
TextImpl text =
(TextImpl) ownerDocument().createTextNode((String) value);
value = text;
text.isFirstChild(true);
text.previousSibling = text;
text.ownerNode = this;
text.isOwned(true);
}
hasStringValue(false);
}
}
/**
* NON-DOM
* set the ownerDocument of this node and its children
*/
protected void setOwnerDocument(CoreDocumentImpl doc) {
if (needsSyncChildren()) {
synchronizeChildren();
}
super.setOwnerDocument(doc);
if (!hasStringValue()) {
for (ChildNode child = (ChildNode) value;
child != null; child = child.nextSibling) {
child.setOwnerDocument(doc);
}
}
}
/**
* NON-DOM: set the type of this attribute to be ID type.
*
* @param id
*/
public void setIdAttribute(boolean id){
if (needsSyncData()) {
synchronizeData();
}
isIdAttribute(id);
}
/** DOM Level 3: isId*/
public boolean isId(){
// REVISIT: should an attribute that is not in the tree return
// isID true?
return isIdAttribute();
}
//
// Node methods
//
public Node cloneNode(boolean deep) {
if (needsSyncChildren()) {
synchronizeChildren();
}
AttrImpl clone = (AttrImpl) super.cloneNode(deep);
// take care of case where there are kids
if (!clone.hasStringValue()) {
// Need to break the association w/ original kids
clone.value = null;
// Cloning an Attribute always clones its children,
// since they represent its value, no matter whether this
// is a deep clone or not
for (Node child = (Node) value; child != null;
child = child.getNextSibling()) {
clone.appendChild(child.cloneNode(true));
}
}
clone.isSpecified(true);
return clone;
}
/**
* A short integer indicating what type of node this is. The named
* constants for this value are defined in the org.w3c.dom.Node interface.
*/
public short getNodeType() {
return Node.ATTRIBUTE_NODE;
}
/**
* Returns the attribute name
*/
public String getNodeName() {
if (needsSyncData()) {
synchronizeData();
}
return name;
}
/**
* Implicit in the rerouting of getNodeValue to getValue is the
* need to redefine setNodeValue, for symmetry's sake. Note that
* since we're explicitly providing a value, Specified should be set
* true.... even if that value equals the default.
*/
public void setNodeValue(String value) throws DOMException {
setValue(value);
}
/**
* @see org.w3c.dom.TypeInfo#getTypeName()
*/
public String getTypeName() {
return (String)type;
}
/**
* @see org.w3c.dom.TypeInfo#getTypeNamespace()
*/
public String getTypeNamespace() {
if (type != null) {
return DTD_URI;
}
return null;
}
/**
* Method getSchemaTypeInfo.
* @return TypeInfo
*/
public TypeInfo getSchemaTypeInfo(){
return this;
}
/**
* In Attribute objects, NodeValue is considered a synonym for
* Value.
*
* @see #getValue()
*/
public String getNodeValue() {
return getValue();
}
//
// Attr methods
//
/**
* In Attributes, NodeName is considered a synonym for the
* attribute's Name
*/
public String getName() {
if (needsSyncData()) {
synchronizeData();
}
return name;
} // getName():String
/**
* The DOM doesn't clearly define what setValue(null) means. I've taken it
* as "remove all children", which from outside should appear
* similar to setting it to the empty string.
*/
public void setValue(String newvalue) {
CoreDocumentImpl ownerDocument = ownerDocument();
if (ownerDocument.errorChecking && isReadOnly()) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NO_MODIFICATION_ALLOWED_ERR", null);
throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, msg);
}
Element ownerElement = getOwnerElement();
String oldvalue = "";
TextImpl textNode = null;
if (needsSyncData()) {
synchronizeData();
}
if (needsSyncChildren()) {
synchronizeChildren();
}
if (value != null) {
if (ownerDocument.getMutationEvents()) {
// Can no longer just discard the kids; they may have
// event listeners waiting for them to disconnect.
if (hasStringValue()) {
oldvalue = (String) value;
// create an actual text node as our child so
// that we can use it in the event
textNode = (TextImpl) ownerDocument.createTextNode((String) value);
value = textNode;
textNode.isFirstChild(true);
textNode.previousSibling = textNode;
textNode.ownerNode = this;
textNode.isOwned(true);
hasStringValue(false);
internalRemoveChild(textNode, true);
}
else {
oldvalue = getValue();
while (value != null) {
internalRemoveChild((Node) value, true);
}
}
}
else {
if (hasStringValue()) {
oldvalue = (String) value;
}
else {
// simply discard children if any
oldvalue = getValue();
// remove ref from first child to last child
ChildNode firstChild = (ChildNode) value;
firstChild.previousSibling = null;
firstChild.isFirstChild(false);
firstChild.ownerNode = ownerDocument;
}
// then remove ref to current value
value = null;
needsSyncChildren(false);
}
if (isIdAttribute() && ownerElement != null) {
ownerDocument.removeIdentifier(oldvalue);
}
}
// Create and add the new one, generating only non-aggregate events
// (There are no listeners on the new Text, but there may be
// capture/bubble listeners on the Attr.
// Note that aggregate events are NOT dispatched here,
// since we need to combine the remove and insert.
isSpecified(true);
if (ownerDocument.getMutationEvents()) {
// if there are any event handlers create a real node or
// reuse the one we synthesized for the remove notifications
// if it exists.
if (textNode == null) {
textNode = (TextImpl) ownerDocument.createTextNode(newvalue);
}
else {
textNode.data = newvalue;
}
internalInsertBefore(textNode, null, true);
hasStringValue(false);
// notify document
ownerDocument.modifiedAttrValue(this, oldvalue);
} else {
// directly store the string
value = newvalue;
hasStringValue(true);
changed();
}
if (isIdAttribute() && ownerElement != null) {
ownerDocument.putIdentifier(newvalue, ownerElement);
}
} // setValue(String)
/**
* The "string value" of an Attribute is its text representation,
* which in turn is a concatenation of the string values of its children.
*/
public String getValue() {
if (needsSyncData()) {
synchronizeData();
}
if (needsSyncChildren()) {
synchronizeChildren();
}
if (value == null) {
return "";
}
if (hasStringValue()) {
return (String) value;
}
ChildNode firstChild = ((ChildNode) value);
String data = null;
if (firstChild.getNodeType() == Node.ENTITY_REFERENCE_NODE){
data = ((EntityReferenceImpl)firstChild).getEntityRefValue();
}
else {
data = firstChild.getNodeValue();
}
ChildNode node = firstChild.nextSibling;
if (node == null || data == null) return (data == null)?"":data;
StringBuffer value = new StringBuffer(data);
while (node != null) {
if (node.getNodeType() == Node.ENTITY_REFERENCE_NODE){
data = ((EntityReferenceImpl)node).getEntityRefValue();
if (data == null) return "";
value.append(data);
}
else {
value.append(node.getNodeValue());
}
node = node.nextSibling;
}
return value.toString();
} // getValue():String
/**
* The "specified" flag is true if and only if this attribute's
* value was explicitly specified in the original document. Note that
* the implementation, not the user, is in charge of this
* property. If the user asserts an Attribute value (even if it ends
* up having the same value as the default), it is considered a
* specified attribute. If you really want to revert to the default,
* delete the attribute from the Element, and the Implementation will
* re-assert the default (if any) in its place, with the appropriate
* specified=false setting.
*/
public boolean getSpecified() {
if (needsSyncData()) {
synchronizeData();
}
return isSpecified();
} // getSpecified():boolean
//
// Attr2 methods
//
/**
* Returns the element node that this attribute is associated with,
* or null if the attribute has not been added to an element.
*
* @see #getOwnerElement
*
* @deprecated Previous working draft of DOM Level 2. New method
* is getOwnerElement().
*/
public Element getElement() {
// if we have an owner, ownerNode is our ownerElement, otherwise it's
// our ownerDocument and we don't have an ownerElement
return (Element) (isOwned() ? ownerNode : null);
}
/**
* Returns the element node that this attribute is associated with,
* or null if the attribute has not been added to an element.
*
* @since WD-DOM-Level-2-19990719
*/
public Element getOwnerElement() {
// if we have an owner, ownerNode is our ownerElement, otherwise it's
// our ownerDocument and we don't have an ownerElement
return (Element) (isOwned() ? ownerNode : null);
}
public void normalize() {
// No need to normalize if already normalized or
// if value is kept as a String.
if (isNormalized() || hasStringValue())
return;
Node kid, next;
ChildNode firstChild = (ChildNode)value;
for (kid = firstChild; kid != null; kid = next) {
next = kid.getNextSibling();
// If kid is a text node, we need to check for one of two
// conditions:
// 1) There is an adjacent text node
// 2) There is no adjacent text node, but kid is
// an empty text node.
if ( kid.getNodeType() == Node.TEXT_NODE )
{
// If an adjacent text node, merge it with kid
if ( next!=null && next.getNodeType() == Node.TEXT_NODE )
{
((Text)kid).appendData(next.getNodeValue());
removeChild( next );
next = kid; // Don't advance; there might be another.
}
else
{
// If kid is empty, remove it
if ( kid.getNodeValue() == null || kid.getNodeValue().length() == 0 ) {
removeChild( kid );
}
}
}
}
isNormalized(true);
} // normalize()
//
// Public methods
//
/** NON-DOM, for use by parser */
public void setSpecified(boolean arg) {
if (needsSyncData()) {
synchronizeData();
}
isSpecified(arg);
} // setSpecified(boolean)
/**
* NON-DOM: used by the parser
* @param type
*/
public void setType (Object type){
this.type = type;
}
//
// Object methods
//
/** NON-DOM method for debugging convenience */
public String toString() {
return getName() + "=" + "\"" + getValue() + "\"";
}
/**
* Test whether this node has any children. Convenience shorthand
* for (Node.getFirstChild()!=null)
*/
public boolean hasChildNodes() {
if (needsSyncChildren()) {
synchronizeChildren();
}
return value != null;
}
/**
* Obtain a NodeList enumerating all children of this node. If there
* are none, an (initially) empty NodeList is returned.
*
* NodeLists are "live"; as children are added/removed the NodeList
* will immediately reflect those changes. Also, the NodeList refers
* to the actual nodes, so changes to those nodes made via the DOM tree
* will be reflected in the NodeList and vice versa.
*
* In this implementation, Nodes implement the NodeList interface and
* provide their own getChildNodes() support. Other DOMs may solve this
* differently.
*/
public NodeList getChildNodes() {
// JKESS: KNOWN ISSUE HERE
if (needsSyncChildren()) {
synchronizeChildren();
}
return this;
} // getChildNodes():NodeList
/** The first child of this Node, or null if none. */
public Node getFirstChild() {
if (needsSyncChildren()) {
synchronizeChildren();
}
makeChildNode();
return (Node) value;
} // getFirstChild():Node
/** The last child of this Node, or null if none. */
public Node getLastChild() {
if (needsSyncChildren()) {
synchronizeChildren();
}
return lastChild();
} // getLastChild():Node
final ChildNode lastChild() {
// last child is stored as the previous sibling of first child
makeChildNode();
return value != null ? ((ChildNode) value).previousSibling : null;
}
final void lastChild(ChildNode node) {
// store lastChild as previous sibling of first child
if (value != null) {
((ChildNode) value).previousSibling = node;
}
}
/**
* Move one or more node(s) to our list of children. Note that this
* implicitly removes them from their previous parent.
*
* @param newChild The Node to be moved to our subtree. As a
* convenience feature, inserting a DocumentNode will instead insert
* all its children.
*
* @param refChild Current child which newChild should be placed
* immediately before. If refChild is null, the insertion occurs
* after all existing Nodes, like appendChild().
*
* @return newChild, in its new state (relocated, or emptied in the case of
* DocumentNode.)
*
* @throws DOMException(HIERARCHY_REQUEST_ERR) if newChild is of a
* type that shouldn't be a child of this node, or if newChild is an
* ancestor of this node.
*
* @throws DOMException(WRONG_DOCUMENT_ERR) if newChild has a
* different owner document than we do.
*
* @throws DOMException(NOT_FOUND_ERR) if refChild is not a child of
* this node.
*
* @throws DOMException(NO_MODIFICATION_ALLOWED_ERR) if this node is
* read-only.
*/
public Node insertBefore(Node newChild, Node refChild)
throws DOMException {
// Tail-call; optimizer should be able to do good things with.
return internalInsertBefore(newChild, refChild, false);
} // insertBefore(Node,Node):Node
/** NON-DOM INTERNAL: Within DOM actions,we sometimes need to be able
* to control which mutation events are spawned. This version of the
* insertBefore operation allows us to do so. It is not intended
* for use by application programs.
*/
Node internalInsertBefore(Node newChild, Node refChild, boolean replace)
throws DOMException {
CoreDocumentImpl ownerDocument = ownerDocument();
boolean errorChecking = ownerDocument.errorChecking;
if (newChild.getNodeType() == Node.DOCUMENT_FRAGMENT_NODE) {
// SLOW BUT SAFE: We could insert the whole subtree without
// juggling so many next/previous pointers. (Wipe out the
// parent's child-list, patch the parent pointers, set the
// ends of the list.) But we know some subclasses have special-
// case behavior they add to insertBefore(), so we don't risk it.
// This approch also takes fewer bytecodes.
// NOTE: If one of the children is not a legal child of this
// node, throw HIERARCHY_REQUEST_ERR before _any_ of the children
// have been transferred. (Alternative behaviors would be to
// reparent up to the first failure point or reparent all those
// which are acceptable to the target node, neither of which is
// as robust. PR-DOM-0818 isn't entirely clear on which it
// recommends?????
// No need to check kids for right-document; if they weren't,
// they wouldn't be kids of that DocFrag.
if (errorChecking) {
for (Node kid = newChild.getFirstChild(); // Prescan
kid != null; kid = kid.getNextSibling()) {
if (!ownerDocument.isKidOK(this, kid)) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "HIERARCHY_REQUEST_ERR", null);
throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, msg);
}
}
}
while (newChild.hasChildNodes()) {
insertBefore(newChild.getFirstChild(), refChild);
}
return newChild;
}
if (newChild == refChild) {
// stupid case that must be handled as a no-op triggering events...
refChild = refChild.getNextSibling();
removeChild(newChild);
insertBefore(newChild, refChild);
return newChild;
}
if (needsSyncChildren()) {
synchronizeChildren();
}
if (errorChecking) {
if (isReadOnly()) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NO_MODIFICATION_ALLOWED_ERR", null);
throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, msg);
}
if (newChild.getOwnerDocument() != ownerDocument) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "WRONG_DOCUMENT_ERR", null);
throw new DOMException(DOMException.WRONG_DOCUMENT_ERR, msg);
}
if (!ownerDocument.isKidOK(this, newChild)) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "HIERARCHY_REQUEST_ERR", null);
throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, msg);
}
// refChild must be a child of this node (or null)
if (refChild != null && refChild.getParentNode() != this) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_FOUND_ERR", null);
throw new DOMException(DOMException.NOT_FOUND_ERR, msg);
}
// Prevent cycles in the tree
// newChild cannot be ancestor of this Node,
// and actually cannot be this
boolean treeSafe = true;
for (NodeImpl a = this; treeSafe && a != null; a = a.parentNode())
{
treeSafe = newChild != a;
}
if (!treeSafe) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "HIERARCHY_REQUEST_ERR", null);
throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, msg);
}
}
makeChildNode(); // make sure we have a node and not a string
// notify document
ownerDocument.insertingNode(this, replace);
// Convert to internal type, to avoid repeated casting
ChildNode newInternal = (ChildNode)newChild;
Node oldparent = newInternal.parentNode();
if (oldparent != null) {
oldparent.removeChild(newInternal);
}
// Convert to internal type, to avoid repeated casting
ChildNode refInternal = (ChildNode) refChild;
// Attach up
newInternal.ownerNode = this;
newInternal.isOwned(true);
// Attach before and after
// Note: firstChild.previousSibling == lastChild!!
ChildNode firstChild = (ChildNode) value;
if (firstChild == null) {
// this our first and only child
value = newInternal; // firstchild = newInternal;
newInternal.isFirstChild(true);
newInternal.previousSibling = newInternal;
}
else {
if (refInternal == null) {
// this is an append
ChildNode lastChild = firstChild.previousSibling;
lastChild.nextSibling = newInternal;
newInternal.previousSibling = lastChild;
firstChild.previousSibling = newInternal;
}
else {
// this is an insert
if (refChild == firstChild) {
// at the head of the list
firstChild.isFirstChild(false);
newInternal.nextSibling = firstChild;
newInternal.previousSibling = firstChild.previousSibling;
firstChild.previousSibling = newInternal;
value = newInternal; // firstChild = newInternal;
newInternal.isFirstChild(true);
}
else {
// somewhere in the middle
ChildNode prev = refInternal.previousSibling;
newInternal.nextSibling = refInternal;
prev.nextSibling = newInternal;
refInternal.previousSibling = newInternal;
newInternal.previousSibling = prev;
}
}
}
changed();
// notify document
ownerDocument.insertedNode(this, newInternal, replace);
checkNormalizationAfterInsert(newInternal);
return newChild;
} // internalInsertBefore(Node,Node,int):Node
/**
* Remove a child from this Node. The removed child's subtree
* remains intact so it may be re-inserted elsewhere.
*
* @return oldChild, in its new state (removed).
*
* @throws DOMException(NOT_FOUND_ERR) if oldChild is not a child of
* this node.
*
* @throws DOMException(NO_MODIFICATION_ALLOWED_ERR) if this node is
* read-only.
*/
public Node removeChild(Node oldChild)
throws DOMException {
// Tail-call, should be optimizable
if (hasStringValue()) {
// we don't have any child per say so it can't be one of them!
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_FOUND_ERR", null);
throw new DOMException(DOMException.NOT_FOUND_ERR, msg);
}
return internalRemoveChild(oldChild, false);
} // removeChild(Node) :Node
/** NON-DOM INTERNAL: Within DOM actions,we sometimes need to be able
* to control which mutation events are spawned. This version of the
* removeChild operation allows us to do so. It is not intended
* for use by application programs.
*/
Node internalRemoveChild(Node oldChild, boolean replace)
throws DOMException {
CoreDocumentImpl ownerDocument = ownerDocument();
if (ownerDocument.errorChecking) {
if (isReadOnly()) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NO_MODIFICATION_ALLOWED_ERR", null);
throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, msg);
}
if (oldChild != null && oldChild.getParentNode() != this) {
String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_FOUND_ERR", null);
throw new DOMException(DOMException.NOT_FOUND_ERR, msg);
}
}
ChildNode oldInternal = (ChildNode) oldChild;
// notify document
ownerDocument.removingNode(this, oldInternal, replace);
// Patch linked list around oldChild
// Note: lastChild == firstChild.previousSibling
if (oldInternal == value) { // oldInternal == firstChild
// removing first child
oldInternal.isFirstChild(false);
// next line is: firstChild = oldInternal.nextSibling
value = oldInternal.nextSibling;
ChildNode firstChild = (ChildNode) value;
if (firstChild != null) {
firstChild.isFirstChild(true);
firstChild.previousSibling = oldInternal.previousSibling;
}
} else {
ChildNode prev = oldInternal.previousSibling;
ChildNode next = oldInternal.nextSibling;
prev.nextSibling = next;
if (next == null) {
// removing last child
ChildNode firstChild = (ChildNode) value;
firstChild.previousSibling = prev;
} else {
// removing some other child in the middle
next.previousSibling = prev;
}
}
// Save previous sibling for normalization checking.
ChildNode oldPreviousSibling = oldInternal.previousSibling();
// Remove oldInternal's references to tree
oldInternal.ownerNode = ownerDocument;
oldInternal.isOwned(false);
oldInternal.nextSibling = null;
oldInternal.previousSibling = null;
changed();
// notify document
ownerDocument.removedNode(this, replace);
checkNormalizationAfterRemove(oldPreviousSibling);
return oldInternal;
} // internalRemoveChild(Node,int):Node
/**
* Make newChild occupy the location that oldChild used to
* have. Note that newChild will first be removed from its previous
* parent, if any. Equivalent to inserting newChild before oldChild,
* then removing oldChild.
*
* @return oldChild, in its new state (removed).
*
* @throws DOMException(HIERARCHY_REQUEST_ERR) if newChild is of a
* type that shouldn't be a child of this node, or if newChild is
* one of our ancestors.
*
* @throws DOMException(WRONG_DOCUMENT_ERR) if newChild has a
* different owner document than we do.
*
* @throws DOMException(NOT_FOUND_ERR) if oldChild is not a child of
* this node.
*
* @throws DOMException(NO_MODIFICATION_ALLOWED_ERR) if this node is
* read-only.
*/
public Node replaceChild(Node newChild, Node oldChild)
throws DOMException {
makeChildNode();
// If Mutation Events are being generated, this operation might
// throw aggregate events twice when modifying an Attr -- once
// on insertion and once on removal. DOM Level 2 does not specify
// this as either desirable or undesirable, but hints that
// aggregations should be issued only once per user request.
// notify document
CoreDocumentImpl ownerDocument = ownerDocument();
ownerDocument.replacingNode(this);
internalInsertBefore(newChild, oldChild, true);
if (newChild != oldChild) {
internalRemoveChild(oldChild, true);
}
// notify document
ownerDocument.replacedNode(this);
return oldChild;
}
//
// NodeList methods
//
/**
* NodeList method: Count the immediate children of this node
* @return int
*/
public int getLength() {
if (hasStringValue()) {
return 1;
}
ChildNode node = (ChildNode) value;
int length = 0;
for (; node != null; node = node.nextSibling) {
length++;
}
return length;
} // getLength():int
/**
* NodeList method: Return the Nth immediate child of this node, or
* null if the index is out of bounds.
* @return org.w3c.dom.Node
* @param index int
*/
public Node item(int index) {
if (hasStringValue()) {
if (index != 0 || value == null) {
return null;
}
else {
makeChildNode();
return (Node) value;
}
}
if (index < 0) {
return null;
}
ChildNode node = (ChildNode) value;
for (int i = 0; i < index && node != null; i++) {
node = node.nextSibling;
}
return node;
} // item(int):Node
//
// DOM3
//
/**
* DOM Level 3 WD- Experimental.
* Override inherited behavior from ParentNode to support deep equal.
* isEqualNode is always deep on Attr nodes.
*/
public boolean isEqualNode(Node arg) {
return super.isEqualNode(arg);
}
/**
* Introduced in DOM Level 3.
* Checks if a type is derived from another by restriction. See:
* http://www.w3.org/TR/DOM-Level-3-Core/core.html#TypeInfo-isDerivedFrom
*
* @param typeNamespaceArg
* The namspace of the ancestor type declaration
* @param typeNameArg
* The name of the ancestor type declaration
* @param derivationMethod
* The derivation method
*
* @return boolean True if the type is derived by restriciton for the
* reference type
*/
public boolean isDerivedFrom(String typeNamespaceArg,
String typeNameArg,
int derivationMethod) {
return false;
}
//
// Public methods
//
/**
* Override default behavior so that if deep is true, children are also
* toggled.
* @see Node
*
* Note: this will not change the state of an EntityReference or its
* children, which are always read-only.
*/
public void setReadOnly(boolean readOnly, boolean deep) {
super.setReadOnly(readOnly, deep);
if (deep) {
if (needsSyncChildren()) {
synchronizeChildren();
}
if (hasStringValue()) {
return;
}
// Recursively set kids
for (ChildNode mykid = (ChildNode) value;
mykid != null;
mykid = mykid.nextSibling) {
if (mykid.getNodeType() != Node.ENTITY_REFERENCE_NODE) {
mykid.setReadOnly(readOnly,true);
}
}
}
} // setReadOnly(boolean,boolean)
//
// Protected methods
//
/**
* Override this method in subclass to hook in efficient
* internal data structure.
*/
protected void synchronizeChildren() {
// By default just change the flag to avoid calling this method again
needsSyncChildren(false);
}
/**
* Checks the normalized state of this node after inserting a child.
* If the inserted child causes this node to be unnormalized, then this
* node is flagged accordingly.
* The conditions for changing the normalized state are:
*
* - The inserted child is a text node and one of its adjacent siblings
* is also a text node.
*
- The inserted child is is itself unnormalized.
*
*
* @param insertedChild the child node that was inserted into this node
*
* @throws NullPointerException if the inserted child is null
*/
void checkNormalizationAfterInsert(ChildNode insertedChild) {
// See if insertion caused this node to be unnormalized.
if (insertedChild.getNodeType() == Node.TEXT_NODE) {
ChildNode prev = insertedChild.previousSibling();
ChildNode next = insertedChild.nextSibling;
// If an adjacent sibling of the new child is a text node,
// flag this node as unnormalized.
if ((prev != null && prev.getNodeType() == Node.TEXT_NODE) ||
(next != null && next.getNodeType() == Node.TEXT_NODE)) {
isNormalized(false);
}
}
else {
// If the new child is not normalized,
// then this node is inherently not normalized.
if (!insertedChild.isNormalized()) {
isNormalized(false);
}
}
} // checkNormalizationAfterInsert(ChildNode)
/**
* Checks the normalized of this node after removing a child.
* If the removed child causes this node to be unnormalized, then this
* node is flagged accordingly.
* The conditions for changing the normalized state are:
*
* - The removed child had two adjacent siblings that were text nodes.
*
*
* @param previousSibling the previous sibling of the removed child, or
* null
*/
void checkNormalizationAfterRemove(ChildNode previousSibling) {
// See if removal caused this node to be unnormalized.
// If the adjacent siblings of the removed child were both text nodes,
// flag this node as unnormalized.
if (previousSibling != null &&
previousSibling.getNodeType() == Node.TEXT_NODE) {
ChildNode next = previousSibling.nextSibling;
if (next != null && next.getNodeType() == Node.TEXT_NODE) {
isNormalized(false);
}
}
} // checkNormalizationAfterRemove(ChildNode)
//
// Serialization methods
//
/** Serialize object. */
private void writeObject(ObjectOutputStream out) throws IOException {
// synchronize chilren
if (needsSyncChildren()) {
synchronizeChildren();
}
// write object
out.defaultWriteObject();
} // writeObject(ObjectOutputStream)
/** Deserialize object. */
private void readObject(ObjectInputStream ois)
throws ClassNotFoundException, IOException {
// perform default deseralization
ois.defaultReadObject();
// hardset synchildren - so we don't try to sync -
// it does not make any sense to try to synchildren when we just
// deserialize object.
needsSyncChildren(false);
} // readObject(ObjectInputStream)
} // class AttrImpl