documentimpl.java

Java的面向对象数据库系统的源代码

/**
 * org/ozone-db/xml/dom/DocumentImpl.java
 *
 * The contents of this file are subject to the OpenXML Public
 * License Version 1.0; you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 * http://www.openxml.org/license.html
 *
 * THIS SOFTWARE IS DISTRIBUTED ON AN "AS IS" BASIS WITHOUT WARRANTY
 * OF ANY KIND, EITHER EXPRESSED OR IMPLIED. THE INITIAL DEVELOPER
 * AND ALL CONTRIBUTORS SHALL NOT BE LIABLE FOR ANY DAMAGES AS A
 * RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. SEE THE LICENSE FOR THE SPECIFIC LANGUAGE GOVERNING
 * RIGHTS AND LIMITATIONS UNDER THE LICENSE.
 *
 * The Initial Developer of this code under the License is Assaf Arkin.
 * Portions created by Assaf Arkin are Copyright (C) 1998, 1999.
 * All Rights Reserved.
 */

/**
 * Changes for Persistent DOM running with ozone are
 * Copyright 1999 by SMB GmbH. All rights reserved.
 */

package org.ozoneDB.xml.dom;

import java.util.*;
import java.io.*;
import org.w3c.dom.*;
import org.ozoneDB.*;
import org.ozoneDB.xml.dom.*;
import org.ozoneDB.xml.util.XMLContainerHelper;


/**
 * Implements an XML document, and also derived to implement an HTML document.
 * Provides access to the top level element in the document ({@link
 * #getDocumentElement}), to the DTD if one exists ({@link #getDoctype},
 * and to all node operations.
 * <P>
 * Several methods create new nodes of all basic types (comment, text, element,
 * etc.). These methods create new nodes but do not place them in the document
 * tree. The nodes may be placed in the document tree using {@link
 * org.w3c.dom.Node#appendChild} or {@link org.w3c.dom.Node#insertBefore}, or
 * they may be placed in some other document tree.
 * <P>
 * Notes:
 * <OL>
 * <LI>Node type is {@link org.w3c.dom.Node#DOCUMENT_NODE}
 * <LI>Node supports childern
 * <LI>Node name is always "#document"
 * <LI>Node does not have a value
 * <LI>Node may not be added to other nodes
 * </OL>
 * This class contains some extensions beyond the DOM API definition. For a list
 * of all extensions, see {@link org.ozoneDB.xml.XMLDocument}.
 *
 *
 * @version $Revision$ $Date$
 * @author <a href="mailto:[e-mail]">Assaf Arkin</a>
 * @see org.w3c.dom.Document
 * @see NodeImpl
 * @see org.w3c.dom.DOMImplementation
 */
public class DocumentImpl extends NodeImpl implements DocumentProxy {

    final static long serialVersionUID = 1;

    private XMLContainerHelper container;


    /**
     * The document type definition of this document (per DOM API). Only available
     * if document was created with a DTD and not available for HTML documents.
     */
    private DocumentTypeProxy _docType;

    /**
     * Holds a reference to the locking thread. When unlocked, this reference is
     * null. This object is used both to designate a lock, identify the locking
     * thread, and perform a {@link Object#wait}.
     *
     * @see #lock
     * @see #unlock
     */
    private Thread _lockThread;


    /**
     * Implement counting on locks, allowing {@link #lock} to be called a
     * multiple number of times, and {@link #unlock} to still retain the lock
     * on the outer calls.
     *
     * @see #lock
     * @see #unlock
     */
    private int _lockCount;


    /**
     * Holds names and classes of application element types. When an element
     * with a particular tag name is created, the matching {@link java.lang.Class}
     * is used to create the element object. This reference is null unless an
     * element has been defined.
     */
    private Hashtable _elementTypes;

    public void writeExternal( ObjectOutput out ) throws IOException {
        super.writeExternal( out );
        out.writeObject ( container );
    }


    public void readExternal( ObjectInput in ) throws IOException, ClassNotFoundException {
        super.readExternal( in );
        container = (XMLContainerHelper)in.readObject();
    }


    /**
     * Set the container of this document. This is needed to find the
     * container that is responsible for a given Node.
     */
    public void setContainer( XMLContainerHelper _container ) {
        this.container = _container;
    }


    /**
     * Get the container of this document. This is needed to find the
     * container that is responsible for a given Node.
     */
    public XMLContainerHelper getContainer() {
        return this.container;
    }


    public Node importNode( Node importedNode, boolean deep ) throws DOMException {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.importNode() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public Element createElementNS( java.lang.String namespaceURI, java.lang.String qualifiedName )
            throws DOMException {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.createElementNS() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public Attr createAttributeNS( java.lang.String namespaceURI, java.lang.String qualifiedName ) throws DOMException {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.createAttributeNS() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public NodeList getElementsByTagNameNS( java.lang.String namespaceURI, java.lang.String localName ) {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.getElementsByTagNameNS() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public Element getElementById( java.lang.String elementId ) {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.getElementById() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public Document createDocument( java.lang.String namespaceURI, java.lang.String qualifiedName,
            DocumentType doctype ) throws DOMException {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.createDocument() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public DocumentType createDocumentType( java.lang.String qualifiedName, java.lang.String publicId,
            java.lang.String systemId ) throws DOMException {
        throw new DOMExceptionImpl( DOMException.NOT_SUPPORTED_ERR,
                "Document.createDocumentType() : ozone's persistent DOM doesn't support DOM level 2 yet." );
    }


    public short getNodeType() {
        return DOCUMENT_NODE;
    }


    public final void setNodeValue( String value ) {
        throw new DOMExceptionImpl( DOMException.NO_DATA_ALLOWED_ERR, "This node type does not support values." );
    }


    public final DocumentType getDoctype() {
        return _docType;
    }


    public final void setDoctype( DocumentType docType ) {
        _docType = (DocumentTypeProxy)docType;
    }


    public final DOMImplementation getImplementation() {
        return this;
    }


    public Element getDocumentElement() {
        Node child;

        // Returns the top-level element in this document. Might not exist, or
        // might be the first of many.
        child = getFirstChild();
        while (child != null) {
            if (child instanceof Element) {
                return (Element)child;
            }
            child = child.getNextSibling();
        }
        return null;
    }


    public void setElementTypes( Hashtable elementTypes ) {
        _elementTypes = elementTypes;
    }


    public Element createElement( String tagName ) throws DOMException {
        ElementProxy elem = null;
        try {
            elem = (ElementProxy)database().createObject( ElementImpl.class.getName() );
            elem.init( this, tagName, null, true );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return elem;
    }


    public final DocumentFragment createDocumentFragment() {
        DocumentFragmentProxy fragment = null;
        try {
            fragment = (DocumentFragmentProxy)database().createObject( DocumentFragmentImpl.class.getName() );
            fragment.init( this, null );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return fragment;
    }


    public final Text createTextNode( String data ) {
        TextProxy text = null;
        try {
            text = (TextProxy)database().createObject( TextImpl.class.getName() );
            text.init( this, data );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return text;
    }


    public final Comment createComment( String data ) {
        CommentProxy comment = null;
        try {
            comment = (CommentProxy)database().createObject( CommentImpl.class.getName() );
            comment.init( this, data );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return comment;
    }


    public final CDATASection createCDATASection( String data ) throws DOMException {
        CDATASectionProxy section = null;
        try {
            section = (CDATASectionProxy)database().createObject( CDATASectionImpl.class.getName() );
            section.init( this, data );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return section;
    }


    public final ProcessingInstruction createProcessingInstruction( String target, String data ) throws DOMException {
        ProcessingInstructionProxy pi = null;
        try {
            pi = (ProcessingInstructionProxy)database().createObject( ProcessingInstructionImpl.class.getName() );
            pi.init( this, target, data );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return pi;
    }


    public final Attr createAttribute( String name ) throws DOMException {
        AttrProxy attr = null;
        try {
            attr = (AttrProxy)database().createObject( AttrImpl.class.getName() );
            attr.init( this, name, "" );
        } catch (Exception except) {
            except.printStackTrace();
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return attr;
    }


    /**
     * Creates an attribute with the default value specified in the DTD.
     * This method is not defined in the DOM but is used by the parser.
     *
     * @param name The name of the attribute
     * @param defValue The default value of the attribute
     */
    public final Attr createAttribute( String name, String defValue ) throws DOMException {
        AttrProxy attr = null;
        try {
            attr = (AttrProxy)database().createObject( AttrImpl.class.getName() );
            attr.init( this, name, defValue == null ? "" : defValue );
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );
        }
        return attr;
    }


    public final EntityReference createEntityReference( String name ) throws DOMException {
        EntityReferenceProxy entity = null;
        try {
            entity = (EntityReferenceProxy)database().createObject( EntityReferenceImpl.class.getName() );
        // entity.init (this, name);
        } catch (Exception except) {
            throw new DOMExceptionImpl( DOMExceptionImpl.PDOM_ERR, except.getMessage() );