org.apache.html.dom.HTMLDocumentImpl Maven / Gradle / Ivy
/*
* 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.html.dom;
import java.io.StringWriter;
import java.lang.reflect.Constructor;
import java.util.Hashtable;
import java.util.Locale;
import org.apache.xerces.dom.DocumentImpl;
import org.apache.xerces.dom.ElementImpl;
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.UserDataHandler;
import org.w3c.dom.html.HTMLBodyElement;
import org.w3c.dom.html.HTMLCollection;
import org.w3c.dom.html.HTMLDocument;
import org.w3c.dom.html.HTMLElement;
import org.w3c.dom.html.HTMLFrameSetElement;
import org.w3c.dom.html.HTMLHeadElement;
import org.w3c.dom.html.HTMLHtmlElement;
import org.w3c.dom.html.HTMLTitleElement;
/**
* Implements an HTML document. Provides access to the top level element in the
* document, its body and title.
*
* 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.
*
* Note: <FRAMESET> documents are not supported at the moment, neither
* are direct document writing ({@link #open}, {@link #write}) and HTTP attribute
* methods ({@link #getURL}, {@link #getCookie}).
*
* @xerces.internal
*
* @version $Revision: 1029415 $ $Date: 2010-10-31 13:02:22 -0400 (Sun, 31 Oct 2010) $
* @author Assaf Arkin
* @see org.w3c.dom.html.HTMLDocument
*/
public class HTMLDocumentImpl
extends DocumentImpl
implements HTMLDocument
{
private static final long serialVersionUID = 4285791750126227180L;
/**
* Holds HTMLCollectionImpl object with live collection of all
* anchors in document. This reference is on demand only once.
*/
private HTMLCollectionImpl _anchors;
/**
* Holds HTMLCollectionImpl object with live collection of all
* forms in document. This reference is on demand only once.
*/
private HTMLCollectionImpl _forms;
/**
* Holds HTMLCollectionImpl object with live collection of all
* images in document. This reference is on demand only once.
*/
private HTMLCollectionImpl _images;
/**
* Holds HTMLCollectionImpl object with live collection of all
* links in document. This reference is on demand only once.
*/
private HTMLCollectionImpl _links;
/**
* Holds HTMLCollectionImpl object with live collection of all
* applets in document. This reference is on demand only once.
*/
private HTMLCollectionImpl _applets;
/**
* Holds string writer used by direct manipulation operation ({@link #open}.
* {@link #write}, etc) to write new contents into the document and parse
* that text into a document tree.
*/
private StringWriter _writer;
/**
* Holds names and classes of HTML 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. For example, <A> matches
* {@link HTMLAnchorElementImpl}. This static table is shared across all
* HTML documents.
*
* @see #createElement
*/
private static Hashtable _elementTypesHTML;
/**
* Signature used to locate constructor of HTML element classes. This
* static array is shared across all HTML documents.
*
* @see #createElement
*/
private static final Class[] _elemClassSigHTML =
new Class[] { HTMLDocumentImpl.class, String.class };
/**
*/
public HTMLDocumentImpl()
{
super();
populateElementTypes();
}
public synchronized Element getDocumentElement()
{
Node html;
Node child;
Node next;
// The document element is the top-level HTML element of the HTML
// document. Only this element should exist at the top level.
// If the HTML element is found, all other elements that might
// precede it are placed inside the HTML element.
html = getFirstChild();
while ( html != null )
{
if ( html instanceof HTMLHtmlElement )
{
// REVISIT: [Q] Why is this code even here? In fact, the
// original code is in error because it will
// try to move ALL nodes to be children of the
// HTML tag. This is not the intended behavior
// for comments and processing instructions
// outside the root element; it will throw a
// hierarchy request error exception for doctype
// nodes; *and* this code shouldn't even be
// needed because the parser should never build
// a document that contains more than a single
// root element, anyway! -Ac
/***
synchronized ( html )
{
child = getFirstChild();
while ( child != null && child != html )
{
next = child.getNextSibling();
html.appendChild( child );
child = next;
}
}
/***/
return (HTMLElement) html;
}
html = html.getNextSibling();
}
// HTML element must exist. Create a new element and dump the
// entire contents of the document into it in the same order as
// they appear now.
html = new HTMLHtmlElementImpl( this, "HTML" );
child = getFirstChild();
while ( child != null )
{
next = child.getNextSibling();
html.appendChild( child );
child = next;
}
appendChild( html );
return (HTMLElement) html;
}
/**
* Obtains the <HEAD> element in the document, creating one if does
* not exist before. The <HEAD> element is the first element in the
* <HTML> in the document. The <HTML> element is obtained by
* calling {@link #getDocumentElement}. If the element does not exist, one
* is created.
*
* Called by {@link #getTitle}, {@link #setTitle}, {@link #getBody} and
* {@link #setBody} to assure the document has the <HEAD> element
* correctly placed.
*
* @return The <HEAD> element
*/
public synchronized HTMLElement getHead()
{
Node head;
Node html;
Node child;
Node next;
// Call getDocumentElement() to get the HTML element that is also the
// top-level element in the document. Get the first element in the
// document that is called HEAD. Work with that.
html = getDocumentElement();
synchronized ( html )
{
head = html.getFirstChild();
while ( head != null && ! ( head instanceof HTMLHeadElement ) )
head = head.getNextSibling();
// HEAD exists but might not be first element in HTML: make sure
// it is and return it.
if ( head != null )
{
synchronized ( head )
{
child = html.getFirstChild();
while ( child != null && child != head )
{
next = child.getNextSibling();
head.insertBefore( child, head.getFirstChild() );
child = next;
}
}
return (HTMLElement) head;
}
// Head does not exist, create a new one, place it at the top of the
// HTML element and return it.
head = new HTMLHeadElementImpl( this, "HEAD" );
html.insertBefore( head, html.getFirstChild() );
}
return (HTMLElement) head;
}
public synchronized String getTitle()
{
HTMLElement head;
NodeList list;
Node title;
// Get the HEAD element and look for the TITLE element within.
// When found, make sure the TITLE is a direct child of HEAD,
// and return the title's text (the Text node contained within).
head = getHead();
list = head.getElementsByTagName( "TITLE" );
if ( list.getLength() > 0 ) {
title = list.item( 0 );
return ( (HTMLTitleElement) title ).getText();
}
// No TITLE found, return an empty string.
return "";
}
public synchronized void setTitle( String newTitle )
{
HTMLElement head;
NodeList list;
Node title;
// Get the HEAD element and look for the TITLE element within.
// When found, make sure the TITLE is a direct child of HEAD,
// and set the title's text (the Text node contained within).
head = getHead();
list = head.getElementsByTagName( "TITLE" );
if ( list.getLength() > 0 ) {
title = list.item( 0 );
if ( title.getParentNode() != head )
head.appendChild( title );
( (HTMLTitleElement) title ).setText( newTitle );
}
else
{
// No TITLE found, create a new element and place it at the end
// of the HEAD element.
title = new HTMLTitleElementImpl( this, "TITLE" );
( (HTMLTitleElement) title ).setText( newTitle );
head.appendChild( title );
}
}
public synchronized HTMLElement getBody()
{
Node html;
Node head;
Node body;
Node child;
Node next;
// Call getDocumentElement() to get the HTML element that is also the
// top-level element in the document. Get the first element in the
// document that is called BODY. Work with that.
html = getDocumentElement();
head = getHead();
synchronized ( html )
{
body = head.getNextSibling();
while ( body != null && ! ( body instanceof HTMLBodyElement )
&& ! ( body instanceof HTMLFrameSetElement ) )
body = body.getNextSibling();
// BODY/FRAMESET exists but might not be second element in HTML
// (after HEAD): make sure it is and return it.
if ( body != null )
{
synchronized ( body )
{
child = head.getNextSibling();
while ( child != null && child != body )
{
next = child.getNextSibling();
body.insertBefore( child, body.getFirstChild() );
child = next;
}
}
return (HTMLElement) body;
}
// BODY does not exist, create a new one, place it in the HTML element
// right after the HEAD and return it.
body = new HTMLBodyElementImpl( this, "BODY" );
html.appendChild( body );
}
return (HTMLElement) body;
}
public synchronized void setBody( HTMLElement newBody )
{
Node html;
Node body;
Node head;
Node child;
NodeList list;
synchronized ( newBody )
{
// Call getDocumentElement() to get the HTML element that is also the
// top-level element in the document. Get the first element in the
// document that is called BODY. Work with that.
html = getDocumentElement();
head = getHead();
synchronized ( html )
{
list = this.getElementsByTagName( "BODY" );
if ( list.getLength() > 0 ) {
// 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 )
{
Element idElement = super.getElementById(elementId);
if (idElement != null) {
return idElement;
}
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) );
}
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 localpart 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 );
}
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 newdoc = new HTMLDocumentImpl();
callUserDataHandlers(this, newdoc, UserDataHandler.NODE_CLONED);
cloneNode(newdoc, deep);
return newdoc;
}
/* (non-Javadoc)
* @see CoreDocumentImpl#canRenameElements()
*/
protected boolean canRenameElements(String newNamespaceURI, String newNodeName, ElementImpl el) {
if (el.getNamespaceURI() != null) {
// element is not HTML:
// can be renamed if not changed to HTML
return newNamespaceURI != null;
}
// check whether a class change is required
Class newClass = (Class) _elementTypesHTML.get(newNodeName.toUpperCase(Locale.ENGLISH));
Class oldClass = (Class) _elementTypesHTML.get(el.getTagName());
return newClass == oldClass;
}
/**
* Recursive method retreives an element by its id attribute.
* Called by {@link #getElementById(String)}.
*
* @param elementId The id 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 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("org.apache.html.dom." + className,
HTMLDocumentImpl.class.getClassLoader(), true) );
} catch ( Exception except ) {
throw new RuntimeException( "HTM019 OpenXML Error: Could not find or execute class " + className + " implementing HTML element " + tagName
+ "\n" + className + "\t" + tagName);
}
}
}