alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (DocumentImpl.java)

This example Java source code file (DocumentImpl.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

attrimpl, documentimpl, dom, enclosingattr, eventlistener, exception, lcount, lentry, mutationeventimpl, nodefilter, nodeimpl, nodeiterator, not_supported_err, string, util, vector

The DocumentImpl.java Java example source code

/*
 * reserved comment block
 * DO NOT REMOVE OR ALTER!
 */
/*
 * Copyright 2001,2002,2004,2005 The Apache Software Foundation.
 *
 * Licensed 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 com.sun.org.apache.xerces.internal.dom;

import java.io.Serializable;
import java.util.Hashtable;
import java.util.Vector;

import com.sun.org.apache.xerces.internal.dom.events.EventImpl;
import com.sun.org.apache.xerces.internal.dom.events.MutationEventImpl;
import org.w3c.dom.UserDataHandler;
import org.w3c.dom.Attr;
import org.w3c.dom.DOMException;
import org.w3c.dom.DOMImplementation;
import org.w3c.dom.DocumentType;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.events.DocumentEvent;
import org.w3c.dom.events.Event;
import org.w3c.dom.events.EventException;
import org.w3c.dom.events.EventListener;
import org.w3c.dom.events.MutationEvent;
import org.w3c.dom.ranges.DocumentRange;
import org.w3c.dom.ranges.Range;
import org.w3c.dom.traversal.DocumentTraversal;
import org.w3c.dom.traversal.NodeFilter;
import org.w3c.dom.traversal.NodeIterator;
import org.w3c.dom.traversal.TreeWalker;


/**
 * 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.
 * <P>
 * 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.
 * <p>
 * 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.
 * <p>
 * <b>Note: When any node in the document is serialized, the
 * entire document is serialized along with it.
 *
 * @xerces.internal
 *
 * @author Arnaud  Le Hors, IBM
 * @author Joe Kesselman, IBM
 * @author Andy Clark, IBM
 * @author Ralf Pfeiffer, IBM
 * @version $Id: DocumentImpl.java,v 1.6 2010/07/20 20:25:24 joehw Exp $
 * @since  PR-DOM-Level-1-19980818.
 */
public class DocumentImpl
    extends CoreDocumentImpl
    implements DocumentTraversal, DocumentEvent, DocumentRange {

    //
    // Constants
    //

    /** Serialization version. */
    static final long serialVersionUID = 515687835542616694L;

    //
    // Data
    //

    /** Iterators */
    // REVISIT: Should this be transient? -Ac
    protected Vector iterators;

     /** Ranges */
    // REVISIT: Should this be transient? -Ac
    protected Vector ranges;

    /** Table for event listeners registered to this document nodes. */
    protected Hashtable eventListeners;

    /** Bypass mutation events firing. */
    protected boolean mutationEvents = false;

    //
    // Constructors
    //

    /**
     * NON-DOM: Actually creating a Document is outside the DOM's spec,
     * since it has to operate in terms of a particular implementation.
     */
    public DocumentImpl() {
        super();
    }

    /** Constructor. */
    public DocumentImpl(boolean grammarAccess) {
        super(grammarAccess);
    }

    /**
     * For DOM2 support.
     * The createDocument factory method is in DOMImplementation.
     */
    public DocumentImpl(DocumentType doctype)
    {
        super(doctype);
    }

    /** For DOM2 support. */
    public DocumentImpl(DocumentType doctype, boolean grammarAccess) {
        super(doctype, grammarAccess);
    }

    //
    // Node methods
    //

    /**
     * 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.
     *
     * @return org.w3c.dom.Node
     * @param deep boolean, iff true replicate children
     */
    public Node cloneNode(boolean deep) {

        DocumentImpl newdoc = new DocumentImpl();
        callUserDataHandlers(this, newdoc, UserDataHandler.NODE_CLONED);
        cloneNode(newdoc, deep);

        // experimental
        newdoc.mutationEvents = mutationEvents;

        return newdoc;

    } // cloneNode(boolean):Node

    /**
     * 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.
     */
    public DOMImplementation getImplementation() {
        // Currently implemented as a singleton, since it's hardcoded
        // information anyway.
        return DOMImplementationImpl.getDOMImplementation();
    }

    //
    // DocumentTraversal methods
    //

    /**
     * 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.
     *
     * @param root The root of the iterator.
     * @param whatToShow The whatToShow mask.
     * @param filter The NodeFilter installed. Null means no filter.
     */
    public NodeIterator createNodeIterator(Node root,
                                           short whatToShow,
                                           NodeFilter filter)
    {
        return createNodeIterator(root, whatToShow, filter, true);
    }

    /**
     * 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.
     *
     * @param root The root of the iterator.
     * @param whatToShow The whatToShow mask.
     * @param filter The NodeFilter installed. Null means no filter.
     * @param entityReferenceExpansion true to expand the contents of
     *                                 EntityReference nodes
     * @since WD-DOM-Level-2-19990923
     */
    public NodeIterator createNodeIterator(Node root,
                                           int whatToShow,
                                           NodeFilter filter,
                                           boolean entityReferenceExpansion)
    {

        if (root == null) {
                  String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_SUPPORTED_ERR", null);
                  throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
        }

        NodeIterator iterator = new NodeIteratorImpl(this,
                                                     root,
                                                     whatToShow,
                                                     filter,
                                                     entityReferenceExpansion);
        if (iterators == null) {
            iterators = new Vector();
        }

        iterators.addElement(iterator);

        return iterator;
    }

    /**
     * NON-DOM extension:
     * Create and return a TreeWalker.
     *
     * @param root The root of the iterator.
     * @param whatToShow The whatToShow mask.
     * @param filter The NodeFilter installed. Null means no filter.
     */
    public TreeWalker createTreeWalker(Node root,
                                       short whatToShow,
                                       NodeFilter filter)
    {
        return createTreeWalker(root, whatToShow, filter, true);
    }
    /**
     * Create and return a TreeWalker.
     *
     * @param root The root of the iterator.
     * @param whatToShow The whatToShow mask.
     * @param filter The NodeFilter installed. Null means no filter.
     * @param entityReferenceExpansion true to expand the contents of
     *                                 EntityReference nodes
     * @since WD-DOM-Level-2-19990923
     */
    public TreeWalker createTreeWalker(Node root,
                                       int whatToShow,
                                       NodeFilter filter,
                                       boolean entityReferenceExpansion)
    {
        if (root == null) {
            String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_SUPPORTED_ERR", null);
            throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
        }
        return new TreeWalkerImpl(root, whatToShow, filter,
                                  entityReferenceExpansion);
    }

    //
    // Not DOM Level 2. Support DocumentTraversal methods.
    //

    /** This is not called by the developer client. The
     *  developer client uses the detach() function on the
     *  NodeIterator itself. <p>
     *
     *  This function is called from the NodeIterator#detach().
     */
     void removeNodeIterator(NodeIterator nodeIterator) {

        if (nodeIterator == null) return;
        if (iterators == null) return;

        iterators.removeElement(nodeIterator);
    }

    //
    // DocumentRange methods
    //
    /**
     */
    public Range createRange() {

        if (ranges == null) {
            ranges = new Vector();
        }

        Range range = new RangeImpl(this);

        ranges.addElement(range);

        return range;

    }

    /** Not a client function. Called by Range.detach(),
     *  so a Range can remove itself from the list of
     *  Ranges.
     */
    void removeRange(Range range) {

        if (range == null) return;
        if (ranges == null) return;

        ranges.removeElement(range);
    }

    /**
     * A method to be called when some text was changed in a text node,
     * so that live objects can be notified.
     */
    void replacedText(NodeImpl node) {
        // notify ranges
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).receiveReplacedText(node);
            }
        }
    }

    /**
     * A method to be called when some text was deleted from a text node,
     * so that live objects can be notified.
     */
    void deletedText(NodeImpl node, int offset, int count) {
        // notify ranges
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).receiveDeletedText(node,
                                                                offset, count);
            }
        }
    }

    /**
     * A method to be called when some text was inserted into a text node,
     * so that live objects can be notified.
     */
    void insertedText(NodeImpl node, int offset, int count) {
        // notify ranges
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).receiveInsertedText(node,
                                                                offset, count);
            }
        }
    }

    /**
     * A method to be called when a text node has been split,
     * so that live objects can be notified.
     */
    void splitData(Node node, Node newNode, int offset) {
        // notify ranges
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).receiveSplitData(node,
                                                              newNode, offset);
            }
        }
    }

    //
    // DocumentEvent methods
    //

    /**
     * Introduced in DOM Level 2. Optional. <p>
     * Create and return Event objects.
     *
     * @param 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.
     * @return Newly created Event
     * @exception DOMException NOT_SUPPORTED_ERR: Raised if the implementation
     * does not support the type of Event interface requested
     * @since WD-DOM-Level-2-19990923
     */
    public Event createEvent(String type)
        throws DOMException {
            if (type.equalsIgnoreCase("Events") || "Event".equals(type))
                return new EventImpl();
            if (type.equalsIgnoreCase("MutationEvents") ||
                "MutationEvent".equals(type))
                return new MutationEventImpl();
            else {
            String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_SUPPORTED_ERR", null);
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
        }
        }

    /**
     * Sets whether the DOM implementation generates mutation events
     * upon operations.
     */
    void setMutationEvents(boolean set) {
        mutationEvents = set;
    }

    /**
     * Returns true if the DOM implementation generates mutation events.
     */
    boolean getMutationEvents() {
        return mutationEvents;
    }

    /**
     * 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.
     */
    protected void setEventListeners(NodeImpl n, Vector listeners) {
        if (eventListeners == null) {
            eventListeners = new Hashtable();
        }
        if (listeners == null) {
            eventListeners.remove(n);
            if (eventListeners.isEmpty()) {
                // stop firing events when there isn't any listener
                mutationEvents = false;
            }
        } else {
            eventListeners.put(n, listeners);
            // turn mutation events on
            mutationEvents = true;
        }
    }

    /**
     * Retreive event listener registered on a given node
     */
    protected Vector getEventListeners(NodeImpl n) {
        if (eventListeners == null) {
            return null;
        }
        return (Vector) eventListeners.get(n);
    }

    //
    // EventTarget support (public and internal)
    //

    //
    // Constants
    //

    /*
     * NON-DOM INTERNAL: Class LEntry is just a struct used to represent
     * event listeners registered with this node. Copies of this object
     * are hung from the nodeListeners Vector.
     * <p>
     * I considered using two vectors -- one for capture,
     * one for bubble -- but decided that since the list of listeners
     * is probably short in most cases, it might not be worth spending
     * the space. ***** REVISIT WHEN WE HAVE MORE EXPERIENCE.
     */
    class LEntry implements Serializable {

        private static final long serialVersionUID = -8426757059492421631L;
        String type;
        EventListener listener;
        boolean useCapture;

        /** NON-DOM INTERNAL: Constructor for Listener list Entry
         * @param type Event name (NOT event group!) to listen for.
         * @param listener Who gets called when event is dispatched
         * @param useCaptue True iff listener is registered on
         *  capturing phase rather than at-target or bubbling
         */
        LEntry(String type, EventListener listener, boolean useCapture)
        {
            this.type = type;
            this.listener = listener;
            this.useCapture = useCapture;
        }

    } // LEntry

    /**
     * Introduced in DOM Level 2. <p> 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.
     * @param node node to add listener to
     * @param type Event name (NOT event group!) to listen for.
     * @param listener Who gets called when event is dispatched
     * @param useCapture True iff listener is registered on
     *  capturing phase rather than at-target or bubbling
     */
    protected void addEventListener(NodeImpl node, String type,
                                    EventListener listener, boolean useCapture)
    {
        // We can't dispatch to blank type-name, and of course we need
        // a listener to dispatch to
        if (type == null || type.equals("") || listener == null)
            return;

        // Each listener may be registered only once per type per phase.
        // Simplest way to code that is to zap the previous entry, if any.
        removeEventListener(node, type, listener, useCapture);

        Vector nodeListeners = getEventListeners(node);
        if(nodeListeners == null) {
            nodeListeners = new Vector();
            setEventListeners(node, nodeListeners);
        }
        nodeListeners.addElement(new LEntry(type, listener, useCapture));

        // Record active listener
        LCount lc = LCount.lookup(type);
        if (useCapture) {
            ++lc.captures;
            ++lc.total;
        }
        else {
            ++lc.bubbles;
            ++lc.total;
        }

    } // addEventListener(NodeImpl,String,EventListener,boolean) :void

    /**
     * Introduced in DOM Level 2. <p> 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.
     * @param node node to remove listener from
     * @param type Event name (NOT event group!) to listen for.
     * @param listener Who gets called when event is dispatched
     * @param useCapture True iff listener is registered on
     *  capturing phase rather than at-target or bubbling
     */
    protected void removeEventListener(NodeImpl node, String type,
                                       EventListener listener,
                                       boolean useCapture)
    {
        // If this couldn't be a valid listener registration, ignore request
        if (type == null || type.equals("") || listener == null)
            return;
        Vector nodeListeners = getEventListeners(node);
        if (nodeListeners == null)
            return;

        // Note that addListener has previously ensured that
        // each listener may be registered only once per type per phase.
        // count-down is OK for deletions!
        for (int i = nodeListeners.size() - 1; i >= 0; --i) {
            LEntry le = (LEntry) nodeListeners.elementAt(i);
            if (le.useCapture == useCapture && le.listener == listener &&
                le.type.equals(type)) {
                nodeListeners.removeElementAt(i);
                // Storage management: Discard empty listener lists
                if (nodeListeners.size() == 0)
                    setEventListeners(node, null);

                // Remove active listener
                LCount lc = LCount.lookup(type);
                if (useCapture) {
                    --lc.captures;
                    --lc.total;
                }
                else {
                    --lc.bubbles;
                    --lc.total;
                }

                break;  // Found it; no need to loop farther.
            }
        }
    } // removeEventListener(NodeImpl,String,EventListener,boolean) :void

    protected void copyEventListeners(NodeImpl src, NodeImpl tgt) {
        Vector nodeListeners = getEventListeners(src);
        if (nodeListeners == null) {
            return;
        }
        setEventListeners(tgt, (Vector) nodeListeners.clone());
    }

    /**
     * Introduced in DOM Level 2. <p>
     * Distribution engine for DOM Level 2 Events.
     * <p>
     * Event propagation runs as follows:
     * <ol>
     * <li>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.
     * <li>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.
     * <li>CAPTURING_PHASE: Ancestors are scanned, root to target, for
     *   Capturing listeners. If found, they are invoked (see below).
     * <li>AT_TARGET:
     *   Event is dispatched to NON-CAPTURING listeners on the
     *   target node. Note that capturing listeners on this node are _not_
     *   invoked.
     * <li>BUBBLING_PHASE: Ancestors are scanned, target to root, for
     *   non-capturing listeners.
     * <li>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.
     * </ol>
     * <p>
     * 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.
     * <p>
     * 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.
     * <p>
     * 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.
     * @param node node to dispatch to
     * @param event the event object to be dispatched to
     *              registered EventListeners
     * @return true if the event's <code>preventDefault()
     *              method was invoked by an EventListener; otherwise false.
    */
    protected boolean dispatchEvent(NodeImpl node, Event event) {
        if (event == null) return false;

        // Can't use anyone else's implementation, since there's no public
        // API for setting the event's processing-state fields.
        EventImpl evt = (EventImpl)event;

        // VALIDATE -- must have been initialized at least once, must have
        // a non-null non-blank name.
        if(!evt.initialized || evt.type == null || evt.type.equals("")) {
            String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "UNSPECIFIED_EVENT_TYPE_ERR", null);
            throw new EventException(EventException.UNSPECIFIED_EVENT_TYPE_ERR, msg);
        }

        // If nobody is listening for this event, discard immediately
        LCount lc = LCount.lookup(evt.getType());
        if (lc.total == 0)
            return evt.preventDefault;

        // INITIALIZE THE EVENT'S DISPATCH STATUS
        // (Note that Event objects are reusable in our implementation;
        // that doesn't seem to be explicitly guaranteed in the DOM, but
        // I believe it is the intent.)
        evt.target = node;
        evt.stopPropagation = false;
        evt.preventDefault = false;

        // Capture pre-event parentage chain, not including target;
        // use pre-event-dispatch ancestors even if event handlers mutate
        // document and change the target's context.
        // Note that this is parents ONLY; events do not
        // cross the Attr/Element "blood/brain barrier".
        // DOMAttrModified. which looks like an exception,
        // is issued to the Element rather than the Attr
        // and causes a _second_ DOMSubtreeModified in the Element's
        // tree.
        Vector pv = new Vector(10,10);
        Node p = node;
        Node n = p.getParentNode();
        while (n != null) {
            pv.addElement(n);
            p = n;
            n = n.getParentNode();
        }

        // CAPTURING_PHASE:
        if (lc.captures > 0) {
            evt.eventPhase = Event.CAPTURING_PHASE;
            // Ancestors are scanned, root to target, for
            // Capturing listeners.
            for (int j = pv.size() - 1; j >= 0; --j) {
                if (evt.stopPropagation)
                    break;  // Someone set the flag. Phase ends.

                // Handle all capturing listeners on this node
                NodeImpl nn = (NodeImpl) pv.elementAt(j);
                evt.currentTarget = nn;
                Vector nodeListeners = getEventListeners(nn);
                if (nodeListeners != null) {
                    Vector nl = (Vector) nodeListeners.clone();
                    // call listeners in the order in which they got registered
                    int nlsize = nl.size();
                    for (int i = 0; i < nlsize; i++) {
                        LEntry le = (LEntry) nl.elementAt(i);
                        if (le.useCapture && le.type.equals(evt.type) &&
                            nodeListeners.contains(le)) {
                            try {
                                le.listener.handleEvent(evt);
                            }
                            catch (Exception e) {
                                // All exceptions are ignored.
                            }
                        }
                    }
                }
            }
        }


        // Both AT_TARGET and BUBBLE use non-capturing listeners.
        if (lc.bubbles > 0) {
            // AT_TARGET PHASE: Event is dispatched to NON-CAPTURING listeners
            // on the target node. Note that capturing listeners on the target
            // node are _not_ invoked, even during the capture phase.
            evt.eventPhase = Event.AT_TARGET;
            evt.currentTarget = node;
            Vector nodeListeners = getEventListeners(node);
            if (!evt.stopPropagation && nodeListeners != null) {
                Vector nl = (Vector) nodeListeners.clone();
                // call listeners in the order in which they got registered
                int nlsize = nl.size();
                for (int i = 0; i < nlsize; i++) {
                    LEntry le = (LEntry) nl.elementAt(i);
                    if (!le.useCapture && le.type.equals(evt.type) &&
                        nodeListeners.contains(le)) {
                        try {
                            le.listener.handleEvent(evt);
                        }
                        catch (Exception e) {
                            // All exceptions are ignored.
                        }
                    }
                }
            }
            // BUBBLING_PHASE: Ancestors are scanned, target to root, for
            // non-capturing listeners. If the event's preventBubbling flag
            // has been set before processing of a node commences, we
            // instead immediately advance to the default phase.
            // Note that not all events bubble.
            if (evt.bubbles) {
                evt.eventPhase = Event.BUBBLING_PHASE;
                int pvsize = pv.size();
                for (int j = 0; j < pvsize; j++) {
                    if (evt.stopPropagation)
                        break;  // Someone set the flag. Phase ends.

                    // Handle all bubbling listeners on this node
                    NodeImpl nn = (NodeImpl) pv.elementAt(j);
                    evt.currentTarget = nn;
                    nodeListeners = getEventListeners(nn);
                    if (nodeListeners != null) {
                        Vector nl = (Vector) nodeListeners.clone();
                        // call listeners in the order in which they got
                        // registered
                        int nlsize = nl.size();
                        for (int i = 0; i < nlsize; i++) {
                            LEntry le = (LEntry) nl.elementAt(i);
                            if (!le.useCapture && le.type.equals(evt.type) &&
                                nodeListeners.contains(le)) {
                                try {
                                    le.listener.handleEvent(evt);
                                }
                                catch (Exception e) {
                                    // All exceptions are ignored.
                                }
                            }
                        }
                    }
                }
            }
        }

        // DEFAULT PHASE: 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.
        // No specific phase value defined, since this is DOM-internal
        if (lc.defaults > 0 && (!evt.cancelable || !evt.preventDefault)) {
            // evt.eventPhase = Event.DEFAULT_PHASE;
            // evt.currentTarget = node;
            // DO_DEFAULT_OPERATION
        }

        return evt.preventDefault;
    } // dispatchEvent(NodeImpl,Event) :boolean

    /**
     * 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.
     * <p>
     * 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.
     * @param n target node (that was directly inserted or removed)
     * @param e event to be sent to that node and its subtree
     */
    protected void dispatchEventToSubtree(Node n, Event e) {

        ((NodeImpl) n).dispatchEvent(e);
        if (n.getNodeType() == Node.ELEMENT_NODE) {
            NamedNodeMap a = n.getAttributes();
            for (int i = a.getLength() - 1; i >= 0; --i)
                dispatchingEventToSubtree(a.item(i), e);
        }
        dispatchingEventToSubtree(n.getFirstChild(), e);

    } // dispatchEventToSubtree(NodeImpl,Node,Event) :void


    /**
     * Dispatches event to the target node's descendents recursively
     *
     * @param n node to dispatch to
     * @param e event to be sent to that node and its subtree
     */
    protected void dispatchingEventToSubtree(Node n, Event e) {
        if (n==null)
                return;

        // ***** Recursive implementation. This is excessively expensive,
        // and should be replaced in conjunction with optimization
        // mentioned above.
        ((NodeImpl) n).dispatchEvent(e);
        if (n.getNodeType() == Node.ELEMENT_NODE) {
            NamedNodeMap a = n.getAttributes();
            for (int i = a.getLength() - 1; i >= 0; --i)
                dispatchingEventToSubtree(a.item(i), e);
        }
        dispatchingEventToSubtree(n.getFirstChild(), e);
        dispatchingEventToSubtree(n.getNextSibling(), e);
    }

    /**
     * NON-DOM INTERNAL: Return object for getEnclosingAttr. Carries
     * (two values, the Attr node affected (if any) and its previous
     * string value. Simple struct, no methods.
     */
    class EnclosingAttr implements Serializable {
        private static final long serialVersionUID = 5208387723391647216L;
        AttrImpl node;
        String oldvalue;
    }

    EnclosingAttr savedEnclosingAttr;

    /**
     * NON-DOM INTERNAL: Convenience wrapper for calling
     * dispatchAggregateEvents when the context was established
     * by <code>savedEnclosingAttr.
     * @param node node to dispatch to
     * @param ea description of Attr affected by current operation
     */
    protected void dispatchAggregateEvents(NodeImpl node, EnclosingAttr ea) {
        if (ea != null)
            dispatchAggregateEvents(node, ea.node, ea.oldvalue,
                                    MutationEvent.MODIFICATION);
        else
            dispatchAggregateEvents(node, null, null, (short) 0);

    } // dispatchAggregateEvents(NodeImpl,EnclosingAttr) :void

    /**
     * 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.
     * <p>
     * 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.
     *
     * @param node The node to dispatch to
     * @param enclosingAttr The Attr node (if any) whose value has been changed
     * as a result of the DOM operation. Null if none such.
     * @param oldValue The String value previously held by the
     * enclosingAttr. Ignored if none such.
     * @param change Type of modification to the attr. See
     * MutationEvent.attrChange
     */
    protected void dispatchAggregateEvents(NodeImpl node,
                                           AttrImpl enclosingAttr,
                                           String oldvalue, short change) {
        // We have to send DOMAttrModified.
        NodeImpl owner = null;
        if (enclosingAttr != null) {
            LCount lc = LCount.lookup(MutationEventImpl.DOM_ATTR_MODIFIED);
            owner = (NodeImpl) enclosingAttr.getOwnerElement();
            if (lc.total > 0) {
                if (owner != null) {
                    MutationEventImpl me =  new MutationEventImpl();
                    me.initMutationEvent(MutationEventImpl.DOM_ATTR_MODIFIED,
                                         true, false, enclosingAttr,
                                         oldvalue,
                                         enclosingAttr.getNodeValue(),
                                         enclosingAttr.getNodeName(),
                                         change);
                    owner.dispatchEvent(me);
                }
            }
        }
        // DOMSubtreeModified gets sent to the lowest common root of a
        // set of changes.
        // "This event is dispatched after all other events caused by the
        // mutation have been fired."
        LCount lc = LCount.lookup(MutationEventImpl.DOM_SUBTREE_MODIFIED);
        if (lc.total > 0) {
            MutationEvent me =  new MutationEventImpl();
            me.initMutationEvent(MutationEventImpl.DOM_SUBTREE_MODIFIED,
                                 true, false, null, null,
                                 null, null, (short) 0);

            // If we're within an Attr, DStM gets sent to the Attr
            // and to its owningElement. Otherwise we dispatch it
            // locally.
            if (enclosingAttr != null) {
                dispatchEvent(enclosingAttr, me);
                if (owner != null)
                    dispatchEvent(owner, me);
            }
            else
                dispatchEvent(node, me);
        }
    } // dispatchAggregateEvents(NodeImpl, AttrImpl,String) :void

    /**
     * NON-DOM INTERNAL: Pre-mutation context check, in
     * preparation for later generating DOMAttrModified events.
     * Determines whether this node is within an Attr
     * @param node node to get enclosing attribute for
     * @return either a description of that Attr, or null if none such.
     */
    protected void saveEnclosingAttr(NodeImpl node) {
        savedEnclosingAttr = null;
        // MUTATION PREPROCESSING AND PRE-EVENTS:
        // If we're within the scope of an Attr and DOMAttrModified
        // was requested, we need to preserve its previous value for
        // that event.
        LCount lc = LCount.lookup(MutationEventImpl.DOM_ATTR_MODIFIED);
        if (lc.total > 0) {
            NodeImpl eventAncestor = node;
            while (true) {
                if (eventAncestor == null)
                    return;
                int type = eventAncestor.getNodeType();
                if (type == Node.ATTRIBUTE_NODE) {
                    EnclosingAttr retval = new EnclosingAttr();
                    retval.node = (AttrImpl) eventAncestor;
                    retval.oldvalue = retval.node.getNodeValue();
                    savedEnclosingAttr = retval;
                    return;
                }
                else if (type == Node.ENTITY_REFERENCE_NODE)
                    eventAncestor = eventAncestor.parentNode();
                else if (type == Node.TEXT_NODE)
                    eventAncestor = eventAncestor.parentNode();
                else
                    return;
                // Any other parent means we're not in an Attr
            }
        }
    } // saveEnclosingAttr(NodeImpl) :void

    /**
     * A method to be called when a character data node has been modified
     */
    void modifyingCharacterData(NodeImpl node, boolean replace) {
        if (mutationEvents) {
                if (!replace) {
                        saveEnclosingAttr(node);
                }
        }
    }

    /**
     * A method to be called when a character data node has been modified
     */
    void modifiedCharacterData(NodeImpl node, String oldvalue, String value, boolean replace) {
        if (mutationEvents) {
                if (!replace) {
                        // MUTATION POST-EVENTS:
                        LCount lc =
                                LCount.lookup(MutationEventImpl.DOM_CHARACTER_DATA_MODIFIED);
                        if (lc.total > 0) {
                                MutationEvent me = new MutationEventImpl();
                                me.initMutationEvent(
                                        MutationEventImpl.DOM_CHARACTER_DATA_MODIFIED,
                                        true, false, null,
                                                                                oldvalue, value, null, (short) 0);
                                dispatchEvent(node, me);
                        }

                        // Subroutine: Transmit DOMAttrModified and DOMSubtreeModified,
                        // if required. (Common to most kinds of mutation)
                        dispatchAggregateEvents(node, savedEnclosingAttr);
                } // End mutation postprocessing
        }
    }

    /**
     * A method to be called when a character data node has been replaced
     */
    void replacedCharacterData(NodeImpl node, String oldvalue, String value) {
        //now that we have finished replacing data, we need to perform the same actions
        //that are required after a character data node has been modified
        //send the value of false for replace parameter so that mutation
        //events if appropriate will be initiated
        modifiedCharacterData(node, oldvalue, value, false);
    }



    /**
     * A method to be called when a node is about to be inserted in the tree.
     */
    void insertingNode(NodeImpl node, boolean replace) {
        if (mutationEvents) {
            if (!replace) {
                saveEnclosingAttr(node);
            }
        }
    }

    /**
     * A method to be called when a node has been inserted in the tree.
     */
    void insertedNode(NodeImpl node, NodeImpl newInternal, boolean replace) {
        if (mutationEvents) {
            // MUTATION POST-EVENTS:
            // "Local" events (non-aggregated)
            // New child is told it was inserted, and where
            LCount lc = LCount.lookup(MutationEventImpl.DOM_NODE_INSERTED);
            if (lc.total > 0) {
                MutationEventImpl me = new MutationEventImpl();
                me.initMutationEvent(MutationEventImpl.DOM_NODE_INSERTED,
                                     true, false, node,
                                     null, null, null, (short) 0);
                dispatchEvent(newInternal, me);
            }

            // If within the Document, tell the subtree it's been added
            // to the Doc.
            lc = LCount.lookup(
                            MutationEventImpl.DOM_NODE_INSERTED_INTO_DOCUMENT);
            if (lc.total > 0) {
                NodeImpl eventAncestor = node;
                if (savedEnclosingAttr != null)
                    eventAncestor = (NodeImpl)
                        savedEnclosingAttr.node.getOwnerElement();
                if (eventAncestor != null) { // Might have been orphan Attr
                    NodeImpl p = eventAncestor;
                    while (p != null) {
                        eventAncestor = p; // Last non-null ancestor
                        // In this context, ancestry includes
                        // walking back from Attr to Element
                        if (p.getNodeType() == ATTRIBUTE_NODE) {
                            p = (NodeImpl) ((AttrImpl)p).getOwnerElement();
                        }
                        else {
                            p = p.parentNode();
                        }
                    }
                    if (eventAncestor.getNodeType() == Node.DOCUMENT_NODE){
                        MutationEventImpl me = new MutationEventImpl();
                        me.initMutationEvent(MutationEventImpl
                                             .DOM_NODE_INSERTED_INTO_DOCUMENT,
                                             false,false,null,null,
                                             null,null,(short)0);
                        dispatchEventToSubtree(newInternal, me);
                    }
                }
            }
            if (!replace) {
                // Subroutine: Transmit DOMAttrModified and DOMSubtreeModified
                // (Common to most kinds of mutation)
                dispatchAggregateEvents(node, savedEnclosingAttr);
            }
        }

        // notify the range of insertions
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).insertedNodeFromDOM(newInternal);
            }
        }
    }

    /**
     * A method to be called when a node is about to be removed from the tree.
     */
    void removingNode(NodeImpl node, NodeImpl oldChild, boolean replace) {

        // notify iterators
        if (iterators != null) {
            int size = iterators.size();
            for (int i = 0; i != size; i++) {
               ((NodeIteratorImpl)iterators.elementAt(i)).removeNode(oldChild);
            }
        }

        // notify ranges
        if (ranges != null) {
            int size = ranges.size();
            for (int i = 0; i != size; i++) {
                ((RangeImpl)ranges.elementAt(i)).removeNode(oldChild);
            }
        }

        // mutation events
        if (mutationEvents) {
            // MUTATION PREPROCESSING AND PRE-EVENTS:
            // If we're within the scope of an Attr and DOMAttrModified
            // was requested, we need to preserve its previous value for
            // that event.
            if (!replace) {
                saveEnclosingAttr(node);
            }
            // Child is told that it is about to be removed
            LCount lc = LCount.lookup(MutationEventImpl.DOM_NODE_REMOVED);
            if (lc.total > 0) {
                MutationEventImpl me= new MutationEventImpl();
                me.initMutationEvent(MutationEventImpl.DOM_NODE_REMOVED,
                                     true, false, node, null,
                                     null, null, (short) 0);
                dispatchEvent(oldChild, me);
            }

            // If within Document, child's subtree is informed that it's
            // losing that status
            lc = LCount.lookup(
                             MutationEventImpl.DOM_NODE_REMOVED_FROM_DOCUMENT);
            if (lc.total > 0) {
                NodeImpl eventAncestor = this;
                if(savedEnclosingAttr != null)
                    eventAncestor = (NodeImpl)
                        savedEnclosingAttr.node.getOwnerElement();
                if (eventAncestor != null) { // Might have been orphan Attr
                    for (NodeImpl p = eventAncestor.parentNode();
                         p != null; p = p.parentNode()) {
                        eventAncestor = p; // Last non-null ancestor
                    }
                    if (eventAncestor.getNodeType() == Node.DOCUMENT_NODE){
                        MutationEventImpl me = new MutationEventImpl();
                        me.initMutationEvent(
                              MutationEventImpl.DOM_NODE_REMOVED_FROM_DOCUMENT,
                                             false, false, null,
                                             null, null, null, (short) 0);
                        dispatchEventToSubtree(oldChild, me);
                    }
                }
            }
        } // End mutation preprocessing
    }

    /**
     * A method to be called when a node has been removed from the tree.
     */
    void removedNode(NodeImpl node, boolean replace) {
        if (mutationEvents) {
            // MUTATION POST-EVENTS:
            // Subroutine: Transmit DOMAttrModified and DOMSubtreeModified,
            // if required. (Common to most kinds of mutation)
            if (!replace) {
                dispatchAggregateEvents(node, savedEnclosingAttr);
            }
        } // End mutation postprocessing
    }

    /**
     * A method to be called when a node is about to be replaced in the tree.
     */
    void replacingNode(NodeImpl node) {
        if (mutationEvents) {
            saveEnclosingAttr(node);
        }
    }

    /**
     * A method to be called when character data is about to be replaced in the tree.
     */
    void replacingData (NodeImpl node) {
        if (mutationEvents) {
                        saveEnclosingAttr(node);
        }
    }

    /**
     * A method to be called when a node has been replaced in the tree.
     */
    void replacedNode(NodeImpl node) {
        if (mutationEvents) {
            dispatchAggregateEvents(node, savedEnclosingAttr);
        }
    }

    /**
     * A method to be called when an attribute value has been modified
     */
    void modifiedAttrValue(AttrImpl attr, String oldvalue) {
        if (mutationEvents) {
            // MUTATION POST-EVENTS:
            dispatchAggregateEvents(attr, attr, oldvalue,
                                    MutationEvent.MODIFICATION);
        }
    }

    /**
     * A method to be called when an attribute node has been set
     */
    void setAttrNode(AttrImpl attr, AttrImpl previous) {
        if (mutationEvents) {
            // MUTATION POST-EVENTS:
            if (previous == null) {
                dispatchAggregateEvents(attr.ownerNode, attr, null,
                                        MutationEvent.ADDITION);
            }
            else {
                dispatchAggregateEvents(attr.ownerNode, attr,
                                        previous.getNodeValue(),
                                        MutationEvent.MODIFICATION);
            }
        }
    }

    /**
     * A method to be called when an attribute node has been removed
     */
    void removedAttrNode(AttrImpl attr, NodeImpl oldOwner, String name) {
        // We can't use the standard dispatchAggregate, since it assumes
        // that the Attr is still attached to an owner. This code is
        // similar but dispatches to the previous owner, "element".
        if (mutationEvents) {
            // If we have to send DOMAttrModified (determined earlier),
            // do so.
            LCount lc = LCount.lookup(MutationEventImpl.DOM_ATTR_MODIFIED);
            if (lc.total > 0) {
                MutationEventImpl me= new MutationEventImpl();
                me.initMutationEvent(MutationEventImpl.DOM_ATTR_MODIFIED,
                                     true, false, attr,
                                     attr.getNodeValue(), null, name,
                                     MutationEvent.REMOVAL);
                dispatchEvent(oldOwner, me);
            }

            // We can hand off to process DOMSubtreeModified, though.
            // Note that only the Element needs to be informed; the
            // Attr's subtree has not been changed by this operation.
            dispatchAggregateEvents(oldOwner, null, null, (short) 0);
        }
    }


    /**
     * A method to be called when an attribute node has been renamed
     */
    void renamedAttrNode(Attr oldAt, Attr newAt) {
        // REVISIT: To be implemented!!!
    }

    /**
     * A method to be called when an element has been renamed
     */
    void renamedElement(Element oldEl, Element newEl) {
        // REVISIT: To be implemented!!!
    }

} // class DocumentImpl

Other Java examples (source code examples)

Here is a short list of links related to this Java DocumentImpl.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.