htmldocumentimpl.java

来自「JAVA的一些源码 JAVA2 STANDARD EDITION DEVELO」· Java 代码 · 共 815 行 · 第 1/2 页

                    // BODY exists but might not follow HEAD in HTML. If not,
                    // make it so and replce it. Start with the HEAD and make
                    // sure the BODY is the first element after the HEAD.
                    body = list.item( 0 );
                    synchronized ( body )
                    {
                        child = head;
                        while ( child != null )
                        {
                            if ( child instanceof Element )
                            {
                                if ( child != body )
                                    html.insertBefore( newBody, child );
                                else
                                    html.replaceChild( newBody, body );
                                return;
                            }
                            child = child.getNextSibling();
                        }
                        html.appendChild( newBody );
                    }
                    return;
                }
                // BODY does not exist, place it in the HTML element
                // right after the HEAD.
                html.appendChild( newBody );
            }
        }
    }


    public synchronized Element getElementById( String elementId )
    {
        return getElementById( elementId, this );
    }


    public NodeList getElementsByName( String elementName )
    {
        return new NameNodeListImpl( this, elementName );
    }


    public final NodeList getElementsByTagName( String tagName )
    {
        return super.getElementsByTagName( tagName.toUpperCase(Locale.ENGLISH) );
    }


    public final NodeList getElementsByTagNameNS( String namespaceURI,
                                                  String localName )
    {
        if ( namespaceURI != null && namespaceURI.length() > 0 )
            return super.getElementsByTagNameNS( namespaceURI, localName.toUpperCase(Locale.ENGLISH) );
        else
            return super.getElementsByTagName( localName.toUpperCase(Locale.ENGLISH) );
    }


    /**
     * Xerces-specific constructor. "localName" is passed in, so we don't need
     * to create a new String for it.
     *
     * @param namespaceURI The namespace URI of the element to
     *                     create.
     * @param qualifiedName The qualified name of the element type to
     *                      instantiate.
     * @param localName     The local name of the element to instantiate.
     * @return Element A new Element object with the following attributes:
     * @throws DOMException INVALID_CHARACTER_ERR: Raised if the specified
     *                      name contains an invalid character.
     */
    public Element createElementNS(String namespaceURI, String qualifiedName,
                                   String localpart)
        throws DOMException
    {
        return createElementNS(namespaceURI, qualifiedName);
    }

    public Element createElementNS( String namespaceURI, String qualifiedName )
    {
        if ( namespaceURI == null || namespaceURI.length() == 0 )
            return createElement( qualifiedName );
        else {
            return super.createElementNS( namespaceURI, qualifiedName );
        }
    }


    public Element createElement( String tagName )
        throws DOMException
    {
        Class        elemClass;
        Constructor    cnst;

        // First, make sure tag name is all upper case, next get the associated
        // element class. If no class is found, generate a generic HTML element.
        // Do so also if an unexpected exception occurs.
        tagName = tagName.toUpperCase(Locale.ENGLISH);
        elemClass = (Class) _elementTypesHTML.get( tagName );
        if ( elemClass != null )
        {
            // Get the constructor for the element. The signature specifies an
            // owner document and a tag name. Use the constructor to instantiate
            // a new object and return it.
            try
            {
                cnst = elemClass.getConstructor( _elemClassSigHTML );
                return (Element) cnst.newInstance( new Object[] { this, tagName } );
            }
            catch ( Exception except )
            {
                Throwable thrw;

                if ( except instanceof java.lang.reflect.InvocationTargetException )
                    thrw = ( (java.lang.reflect.InvocationTargetException) except ).getTargetException();
                else
                    thrw = except;
//                System.out.println( "Exception " + thrw.getClass().getName() );
//                System.out.println( thrw.getMessage() );

                throw new IllegalStateException( "HTM15 Tag '" + tagName + "' associated with an Element class that failed to construct.\n" + tagName);
            }
        }
        return new HTMLElementImpl( this, tagName );
    }


    /**
     * Creates an Attribute having this Document as its OwnerDoc.
     * Overrides {@link DocumentImpl#createAttribute} and returns
     * and attribute whose name is lower case.
     *
     * @param name The name of the attribute
     * @return An attribute whose name is all lower case
     * @throws DOMException(INVALID_NAME_ERR) if the attribute name
     *   is not acceptable
     */
    public Attr createAttribute( String name )
        throws DOMException
    {
        return super.createAttribute( name.toLowerCase(Locale.ENGLISH) );
    }


    public String getReferrer()
    {
        // Information not available on server side.
        return null;
    }


    public String getDomain()
    {
        // Information not available on server side.
        return null;
    }


    public String getURL()
    {
        // Information not available on server side.
        return null;
    }


    public String getCookie()
    {
        // Information not available on server side.
        return null;
    }


    public void setCookie( String cookie )
    {
        // Information not available on server side.
    }


    public HTMLCollection getImages()
    {
        // For more information see HTMLCollection#collectionMatch
        if ( _images == null )
            _images = new HTMLCollectionImpl( getBody(), HTMLCollectionImpl.IMAGE );
        return _images;
    }


    public HTMLCollection getApplets()
    {
        // For more information see HTMLCollection#collectionMatch
        if ( _applets == null )
            _applets = new HTMLCollectionImpl( getBody(), HTMLCollectionImpl.APPLET );
        return _applets;
    }


    public HTMLCollection getLinks()
    {
        // For more information see HTMLCollection#collectionMatch
        if ( _links == null )
            _links = new HTMLCollectionImpl( getBody(), HTMLCollectionImpl.LINK );
        return _links;
    }


    public HTMLCollection getForms()
    {
        // For more information see HTMLCollection#collectionMatch
        if ( _forms == null )
            _forms = new HTMLCollectionImpl( getBody(), HTMLCollectionImpl.FORM );
        return _forms;
    }


    public HTMLCollection getAnchors()
    {
        // For more information see HTMLCollection#collectionMatch
        if ( _anchors == null )
            _anchors = new HTMLCollectionImpl( getBody(), HTMLCollectionImpl.ANCHOR );
        return _anchors;
    }


    public void open()
    {
        // When called an in-memory is prepared. The document tree is still
        // accessible the old way, until this writer is closed.
        if ( _writer == null )
            _writer = new StringWriter();
    }


    public void close()
    {
        // ! NOT IMPLEMENTED, REQUIRES PARSER !
        if ( _writer != null )
        {
            _writer = null;
        }
    }


    public void write( String text )
    {
        // Write a string into the in-memory writer.
        if ( _writer != null )
            _writer.write( text );
    }


    public void writeln( String text )
    {
        // Write a line into the in-memory writer.
        if ( _writer != null )
            _writer.write( text + "\n" );
    }


    public Node cloneNode( boolean deep )
    {
        HTMLDocumentImpl    clone;
        NodeImpl            node;

        clone = new HTMLDocumentImpl();
        if ( deep ) {
            node = (NodeImpl) getFirstChild();
            while ( node != null ) {
                clone.appendChild( clone.importNode( node, true ) );
                node = (NodeImpl) node.getNextSibling();
            }
        }
        return clone;
    }


    /**
     * Recursive method retreives an element by its <code>id</code> attribute.
     * Called by {@link #getElementById(String)}.
     *
     * @param elementId The <code>id</code> value to look for
     * @return The node in which to look for
     */
    private Element getElementById( String elementId, Node node )
    {
        Node    child;
        Element    result;

        child = node.getFirstChild();
        while ( child != null )
        {
            if ( child instanceof Element )
            {
                if ( elementId.equals( ( (Element) child ).getAttribute( "id" ) ) )
                    return (Element) child;
                result = getElementById( elementId, child );
                if ( result != null )
                    return result;
            }
            child = child.getNextSibling();
        }
        return null;
    }


    /**
     * Called by the constructor to populate the element types list (see {@link
     * #_elementTypesHTML}). Will be called multiple times but populate the list
     * only the first time. Replacement for static constructor.
     */
    private synchronized static void populateElementTypes()
    {
        // This class looks like it is due to some strange
        // (read: inconsistent) JVM bugs.
        // Initially all this code was placed in the static constructor,
        // but that caused some early JVMs (1.1) to go mad, and if a
        // class could not be found (as happened during development),
        // the JVM would die.
        // Bertrand Delacretaz <[e-mail]> pointed out
        // several configurations where HTMLAnchorElementImpl.class
        // failed, forcing me to revert back to Class.forName().

        if ( _elementTypesHTML != null )
            return;
        _elementTypesHTML = new Hashtable( 63 );
        populateElementType( "A", "HTMLAnchorElementImpl" );
        populateElementType( "APPLET", "HTMLAppletElementImpl" );
        populateElementType( "AREA", "HTMLAreaElementImpl" );
        populateElementType( "BASE",  "HTMLBaseElementImpl" );
        populateElementType( "BASEFONT", "HTMLBaseFontElementImpl" );
        populateElementType( "BLOCKQUOTE", "HTMLQuoteElementImpl" );
        populateElementType( "BODY", "HTMLBodyElementImpl" );
        populateElementType( "BR", "HTMLBRElementImpl" );
        populateElementType( "BUTTON", "HTMLButtonElementImpl" );
        populateElementType( "DEL", "HTMLModElementImpl" );
        populateElementType( "DIR", "HTMLDirectoryElementImpl" );
        populateElementType( "DIV",  "HTMLDivElementImpl" );
        populateElementType( "DL", "HTMLDListElementImpl" );
        populateElementType( "FIELDSET", "HTMLFieldSetElementImpl" );
        populateElementType( "FONT", "HTMLFontElementImpl" );
        populateElementType( "FORM", "HTMLFormElementImpl" );
        populateElementType( "FRAME","HTMLFrameElementImpl" );
        populateElementType( "FRAMESET", "HTMLFrameSetElementImpl" );
        populateElementType( "HEAD", "HTMLHeadElementImpl" );
        populateElementType( "H1", "HTMLHeadingElementImpl" );
        populateElementType( "H2", "HTMLHeadingElementImpl" );
        populateElementType( "H3", "HTMLHeadingElementImpl" );
        populateElementType( "H4", "HTMLHeadingElementImpl" );
        populateElementType( "H5", "HTMLHeadingElementImpl" );
        populateElementType( "H6", "HTMLHeadingElementImpl" );
        populateElementType( "HR", "HTMLHRElementImpl" );
        populateElementType( "HTML", "HTMLHtmlElementImpl" );
        populateElementType( "IFRAME", "HTMLIFrameElementImpl" );
        populateElementType( "IMG", "HTMLImageElementImpl" );
        populateElementType( "INPUT", "HTMLInputElementImpl" );
        populateElementType( "INS", "HTMLModElementImpl" );
        populateElementType( "ISINDEX", "HTMLIsIndexElementImpl" );
        populateElementType( "LABEL", "HTMLLabelElementImpl" );
        populateElementType( "LEGEND", "HTMLLegendElementImpl" );
        populateElementType( "LI", "HTMLLIElementImpl" );
        populateElementType( "LINK", "HTMLLinkElementImpl" );
        populateElementType( "MAP", "HTMLMapElementImpl" );
        populateElementType( "MENU", "HTMLMenuElementImpl" );
        populateElementType( "META", "HTMLMetaElementImpl" );
        populateElementType( "OBJECT", "HTMLObjectElementImpl" );
        populateElementType( "OL", "HTMLOListElementImpl" );
        populateElementType( "OPTGROUP", "HTMLOptGroupElementImpl" );
        populateElementType( "OPTION", "HTMLOptionElementImpl" );
        populateElementType( "P", "HTMLParagraphElementImpl" );
        populateElementType( "PARAM", "HTMLParamElementImpl" );
        populateElementType( "PRE", "HTMLPreElementImpl" );
        populateElementType( "Q", "HTMLQuoteElementImpl" );
        populateElementType( "SCRIPT", "HTMLScriptElementImpl" );
        populateElementType( "SELECT", "HTMLSelectElementImpl" );
        populateElementType( "STYLE", "HTMLStyleElementImpl" );
        populateElementType( "TABLE", "HTMLTableElementImpl" );
        populateElementType( "CAPTION", "HTMLTableCaptionElementImpl" );
        populateElementType( "TD", "HTMLTableCellElementImpl" );
        populateElementType( "TH", "HTMLTableCellElementImpl" );
        populateElementType( "COL", "HTMLTableColElementImpl" );
        populateElementType( "COLGROUP", "HTMLTableColElementImpl" );
        populateElementType( "TR", "HTMLTableRowElementImpl" );
        populateElementType( "TBODY", "HTMLTableSectionElementImpl" );
        populateElementType( "THEAD", "HTMLTableSectionElementImpl" );
        populateElementType( "TFOOT", "HTMLTableSectionElementImpl" );
        populateElementType( "TEXTAREA", "HTMLTextAreaElementImpl" );
        populateElementType( "TITLE", "HTMLTitleElementImpl" );
        populateElementType( "UL", "HTMLUListElementImpl" );
    }


    private static void populateElementType( String tagName, String className )
    {
        try {
            _elementTypesHTML.put( tagName,
                ObjectFactory.findProviderClass("com.sun.org.apache.html.internal.dom." + className,
                    HTMLDocumentImpl.class.getClassLoader(), true) );
        } catch ( Exception except ) {
            new RuntimeException( "HTM019 OpenXML Error: Could not find or execute class " + className + " implementing HTML element " + tagName
                                  + "\n" + className + "\t" + tagName);
        }
    }


}