org.randomcoder.content
Class XHTMLReader

java.lang.Object
  org.xml.sax.helpers.XMLFilterImpl
      org.randomcoder.content.XHTMLReader

All Implemented Interfaces:

ContentHandler, DTDHandler, EntityResolver, ErrorHandler, XMLFilter, XMLReader

public class XHTMLReader
extends XMLFilterImpl

XMLFilter implementation which filters out dangerous and/or unwanted markup from the input XML.

This class implements a large subset of XHTML (minus dangerous, deprecated, or otherwise undesirable content). Tag and attribute names are canonicalized, non-semantic markup is converted to semantic, and disallowed elements, their children, and attributes are removed.

 Copyright (c) 2006, Craig Condit. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:
 
   * Redistributions of source code must retain the above copyright notice,
     this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above copyright notice,
     this list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.
     
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 POSSIBILITY OF SUCH DAMAGE.
 

Constructor Summary

XHTMLReader(XMLReader parent, Set<String> allowedClasses, URL baseUrl)
Creates a new XHTMLReader.

Method Summary

void	characters(char[] ch, int start, int length) Parses character data.
void	endDocument() Marks the end of the current document.
void	endElement(String uri, String localName, String qName) Marks the end of the current element.
void	endPrefixMapping(String prefix) Ends the current prefix mapping.
void	ignorableWhitespace(char[] ch, int start, int length) Processes ignorable whitespace.
void	notationDecl(String name, String publicId, String systemId) Processes a notation declaration.
void	processingInstruction(String target, String data) Handles processing instructions.
InputSource	resolveEntity(String publicId, String systemId) Resolves an entity.
void	skippedEntity(String name) Skips an entity.
void	startDocument() Marks the beginning of the current document.
void	startElement(String uri, String localName, String qName, Attributes atts) Marks the start of an element.
void	startPrefixMapping(String prefix, String uri) Starts mapping a prefix.
void	unparsedEntityDecl(String name, String publicId, String systemId, String notationName) Handles unparsed entity declaractions.

Methods inherited from class org.xml.sax.helpers.XMLFilterImpl

error, fatalError, getContentHandler, getDTDHandler, getEntityResolver, getErrorHandler, getFeature, getParent, getProperty, parse, parse, setContentHandler, setDocumentLocator, setDTDHandler, setEntityResolver, setErrorHandler, setFeature, setParent, setProperty, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

XHTMLReader

public XHTMLReader(XMLReader parent,
                   Set<String> allowedClasses,
                   URL baseUrl)

Creates a new XHTMLReader.

Parameters:

parent - parent reader to wrap

allowedClasses - set of allowed css classes

baseUrl - base URL for links

Method Detail

startDocument

public void startDocument()
                   throws SAXException

Marks the beginning of the current document.

Specified by:

startDocument in interface ContentHandler

Overrides:

startDocument in class XMLFilterImpl

Throws:

SAXException - if an error occurs

endDocument

public void endDocument()
                 throws SAXException

Marks the end of the current document.

Specified by:

endDocument in interface ContentHandler

Overrides:

endDocument in class XMLFilterImpl

Throws:

SAXException - if an error occurs

startElement

public void startElement(String uri,
                         String localName,
                         String qName,
                         Attributes atts)
                  throws SAXException

Marks the start of an element.

Specified by:

startElement in interface ContentHandler

Overrides:

startElement in class XMLFilterImpl

Parameters:

uri - URI of element

localName - local part

qName - qualified name

atts - list of attributes

Throws:

SAXException - if an error occurs

endElement

public void endElement(String uri,
                       String localName,
                       String qName)
                throws SAXException

Marks the end of the current element.

Specified by:

endElement in interface ContentHandler

Overrides:

endElement in class XMLFilterImpl

Parameters:

uri - URI of the current element

localName - local part

qName - fully qualified name

Throws:

SAXException - if an error occurs

characters

public void characters(char[] ch,
                       int start,
                       int length)
                throws SAXException

Parses character data.

Specified by:

characters in interface ContentHandler

Overrides:

characters in class XMLFilterImpl

Parameters:

ch - character buffer

start - starting offset in buffer

length - number of characters to process

Throws:

SAXException - if an error occurs

ignorableWhitespace

public void ignorableWhitespace(char[] ch,
                                int start,
                                int length)
                         throws SAXException

Processes ignorable whitespace.

Specified by:

ignorableWhitespace in interface ContentHandler

Overrides:

ignorableWhitespace in class XMLFilterImpl

Parameters:

ch - character buffer to read

start - starting offset in buffer

length - number of characters to read

Throws:

SAXException - if an error occurs

processingInstruction

public void processingInstruction(String target,
                                  String data)
                           throws SAXException

Handles processing instructions.

Specified by:

processingInstruction in interface ContentHandler

Overrides:

processingInstruction in class XMLFilterImpl

Parameters:

target - target of processing instruction

data - associated data

Throws:

SAXException - if an error occurs

unparsedEntityDecl

public void unparsedEntityDecl(String name,
                               String publicId,
                               String systemId,
                               String notationName)
                        throws SAXException

Handles unparsed entity declaractions.

Specified by:

unparsedEntityDecl in interface DTDHandler

Overrides:

unparsedEntityDecl in class XMLFilterImpl

Parameters:

name - name of entity

publicId - public identifier

systemId - system identifier

notationName - notation name

Throws:

SAXException - if an error occurs

resolveEntity

public InputSource resolveEntity(String publicId,
                                 String systemId)
                          throws SAXException,
                                 IOException

Resolves an entity.

Specified by:

resolveEntity in interface EntityResolver

Overrides:

resolveEntity in class XMLFilterImpl

Parameters:

publicId - public identifier

systemId - system identifier

Returns:

InputSource pointing to the requested entity

Throws:

SAXException - if an error occurs

IOException

skippedEntity

public void skippedEntity(String name)
                   throws SAXException

Skips an entity.

Specified by:

skippedEntity in interface ContentHandler

Overrides:

skippedEntity in class XMLFilterImpl

Parameters:

name - name of entity to skip

Throws:

SAXException - if an error occurs

notationDecl

public void notationDecl(String name,
                         String publicId,
                         String systemId)
                  throws SAXException

Processes a notation declaration.

Specified by:

notationDecl in interface DTDHandler

Overrides:

notationDecl in class XMLFilterImpl

Parameters:

name - notation name

publicId - public identifier

systemId - system identifier

Throws:

SAXException - if an error occurs

startPrefixMapping

public void startPrefixMapping(String prefix,
                               String uri)
                        throws SAXException

Starts mapping a prefix.

Specified by:

startPrefixMapping in interface ContentHandler

Overrides:

startPrefixMapping in class XMLFilterImpl

Parameters:

prefix - name of prefix to map

uri - URI of prefix to map

Throws:

SAXException - if an error occurs

endPrefixMapping

public void endPrefixMapping(String prefix)
                      throws SAXException

Ends the current prefix mapping.

Specified by:

endPrefixMapping in interface ContentHandler

Overrides:

endPrefixMapping in class XMLFilterImpl

Parameters:

prefix - prefix to be mapped

Throws:

SAXException - if an error occurs