Package org.codelibs.nekohtml.filters

Class Purifier

java.lang.Object

org.codelibs.nekohtml.filters.DefaultFilter

org.codelibs.nekohtml.filters.Purifier

All Implemented Interfaces:

org.apache.xerces.xni.parser.XMLComponent, org.apache.xerces.xni.parser.XMLDocumentFilter, org.apache.xerces.xni.parser.XMLDocumentSource, org.apache.xerces.xni.XMLDocumentHandler, HTMLComponent

public class Purifier
extends DefaultFilter

This filter purifies the HTML input to ensure XML well-formedness. The purification process includes:

• fixing illegal characters in the document, including
  • element and attribute names,
  • processing instruction target and data,
  • document text;
• ensuring the string "--" does not appear in the content of a comment;
• ensuring the string "]]>" does not appear in the content of a CDATA section;
• ensuring that the XML declaration has required pseudo-attributes and that the values are correct; and
• synthesized missing namespace bindings.

Illegal characters in XML names are converted to the character sequence "_u####_" where "####" is the value of the Unicode character represented in hexadecimal. Whereas illegal characters appearing in document content is converted to the character sequence "\\u####".

In comments, the character '-' is replaced by the character sequence "- " to prevent "--" from ever appearing in the comment content. For CDATA sections, the character ']' is replaced by the character sequence "] " to prevent "]]" from appearing.

The URI used for synthesized namespace bindings is "http://cyberneko.org/html/ns/synthesized/number" where number is generated to ensure uniqueness.

Version:

$Id: Purifier.java,v 1.5 2005/02/14 03:56:54 andyc Exp $

Author:

Andy Clark

Field Summary

Fields

Modifier and Type	Field	Description
protected static java.lang.String	AUGMENTATIONS	Include infoset augmentations.
protected boolean	fAugmentations	Augmentations.
protected boolean	fInCDATASection	True if inside a CDATA section.
protected org.apache.xerces.xni.NamespaceContext	fNamespaceContext	Namespace information.
protected boolean	fNamespaces	Namespaces.
protected java.lang.String	fPublicId	Public identifier of doctype declaration.
protected boolean	fSeenDoctype	True if the doctype declaration was seen.
protected boolean	fSeenRootElement	True if root element was seen.
protected int	fSynthesizedNamespaceCount	Synthesized namespace binding count.
protected java.lang.String	fSystemId	System identifier of doctype declaration.
protected static java.lang.String	NAMESPACES	Namespaces.
protected static HTMLEventInfo	SYNTHESIZED_ITEM	Synthesized event info item.
static java.lang.String	SYNTHESIZED_NAMESPACE_PREFX	Synthesized namespace binding prefix.

Fields inherited from class org.codelibs.nekohtml.filters.DefaultFilter

fDocumentHandler, fDocumentSource

Constructor Summary

Constructors

Constructor	Description
Purifier()

Method Summary

Modifier and Type	Method	Description
void	characters(org.apache.xerces.xni.XMLString text, org.apache.xerces.xni.Augmentations augs)	Characters.
void	comment(org.apache.xerces.xni.XMLString text, org.apache.xerces.xni.Augmentations augs)	Comment.
void	doctypeDecl(java.lang.String root, java.lang.String pubid, java.lang.String sysid, org.apache.xerces.xni.Augmentations augs)	Doctype declaration.
void	emptyElement(org.apache.xerces.xni.QName element, org.apache.xerces.xni.XMLAttributes attrs, org.apache.xerces.xni.Augmentations augs)	Empty element.
void	endCDATA(org.apache.xerces.xni.Augmentations augs)	End CDATA section.
void	endElement(org.apache.xerces.xni.QName element, org.apache.xerces.xni.Augmentations augs)	End element.
protected void	handleStartDocument()	Handle start document.
protected void	handleStartElement(org.apache.xerces.xni.QName element, org.apache.xerces.xni.XMLAttributes attrs)	Handle start element.
void	processingInstruction(java.lang.String target, org.apache.xerces.xni.XMLString data, org.apache.xerces.xni.Augmentations augs)	Processing instruction.
protected java.lang.String	purifyName(java.lang.String name, boolean localpart)	Purify name.
protected org.apache.xerces.xni.QName	purifyQName(org.apache.xerces.xni.QName qname)	Purify qualified name.
protected org.apache.xerces.xni.XMLString	purifyText(org.apache.xerces.xni.XMLString text)	Purify content.
void	reset(org.apache.xerces.xni.parser.XMLComponentManager manager)	Resets the component.
void	startCDATA(org.apache.xerces.xni.Augmentations augs)	Start CDATA section.
void	startDocument(org.apache.xerces.xni.XMLLocator locator, java.lang.String encoding, org.apache.xerces.xni.Augmentations augs)	Start document.
void	startDocument(org.apache.xerces.xni.XMLLocator locator, java.lang.String encoding, org.apache.xerces.xni.NamespaceContext nscontext, org.apache.xerces.xni.Augmentations augs)	Start document.
void	startElement(org.apache.xerces.xni.QName element, org.apache.xerces.xni.XMLAttributes attrs, org.apache.xerces.xni.Augmentations augs)	Start element.
protected void	synthesizeBinding(org.apache.xerces.xni.XMLAttributes attrs, java.lang.String ns)	Synthesize namespace binding.
protected org.apache.xerces.xni.Augmentations	synthesizedAugs()	Returns an augmentations object with a synthesized item added.
protected static java.lang.String	toHexString(int c, int padlen)	Returns a padded hexadecimal string for the given value.
void	xmlDecl(java.lang.String version, java.lang.String encoding, java.lang.String standalone, org.apache.xerces.xni.Augmentations augs)	XML declaration.

Methods inherited from class org.codelibs.nekohtml.filters.DefaultFilter

endDocument, endGeneralEntity, endPrefixMapping, getDocumentHandler, getDocumentSource, getFeatureDefault, getPropertyDefault, getRecognizedFeatures, getRecognizedProperties, ignorableWhitespace, merge, setDocumentHandler, setDocumentSource, setFeature, setProperty, startGeneralEntity, startPrefixMapping, textDecl

Methods inherited from class java.lang.Object

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

Field Detail

SYNTHESIZED_NAMESPACE_PREFX

public static final java.lang.String SYNTHESIZED_NAMESPACE_PREFX

Synthesized namespace binding prefix.

See Also:

Constant Field Values

NAMESPACES

protected static final java.lang.String NAMESPACES

Namespaces.

See Also:

Constant Field Values

AUGMENTATIONS

protected static final java.lang.String AUGMENTATIONS

Include infoset augmentations.

See Also:

Constant Field Values

SYNTHESIZED_ITEM

protected static final HTMLEventInfo SYNTHESIZED_ITEM

Synthesized event info item.

fNamespaces

protected boolean fNamespaces

Namespaces.

fAugmentations

protected boolean fAugmentations

Augmentations.

fSeenDoctype

protected boolean fSeenDoctype

True if the doctype declaration was seen.

fSeenRootElement

protected boolean fSeenRootElement

True if root element was seen.

fInCDATASection

protected boolean fInCDATASection

True if inside a CDATA section.

fPublicId

protected java.lang.String fPublicId

Public identifier of doctype declaration.

fSystemId

protected java.lang.String fSystemId

System identifier of doctype declaration.

fNamespaceContext

protected org.apache.xerces.xni.NamespaceContext fNamespaceContext

Namespace information.

fSynthesizedNamespaceCount

protected int fSynthesizedNamespaceCount

Synthesized namespace binding count.

Constructor Detail

Purifier

public Purifier()

Method Detail

reset

public void reset(org.apache.xerces.xni.parser.XMLComponentManager manager)

Description copied from class: DefaultFilter

Resets the component. The component can query the component manager about any features and properties that affect the operation of the component.

Specified by:

reset in interface org.apache.xerces.xni.parser.XMLComponent

Overrides:

reset in class DefaultFilter

Parameters:

manager - The component manager.

startDocument

public void startDocument(org.apache.xerces.xni.XMLLocator locator,
                          java.lang.String encoding,
                          org.apache.xerces.xni.Augmentations augs)

Start document.

Overrides:

startDocument in class DefaultFilter

startDocument

public void startDocument(org.apache.xerces.xni.XMLLocator locator,
                          java.lang.String encoding,
                          org.apache.xerces.xni.NamespaceContext nscontext,
                          org.apache.xerces.xni.Augmentations augs)

Start document.

Specified by:

startDocument in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

startDocument in class DefaultFilter

xmlDecl

public void xmlDecl(java.lang.String version,
                    java.lang.String encoding,
                    java.lang.String standalone,
                    org.apache.xerces.xni.Augmentations augs)

XML declaration.

Specified by:

xmlDecl in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

xmlDecl in class DefaultFilter

comment

public void comment(org.apache.xerces.xni.XMLString text,
                    org.apache.xerces.xni.Augmentations augs)

Comment.

Specified by:

comment in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

comment in class DefaultFilter

processingInstruction

public void processingInstruction(java.lang.String target,
                                  org.apache.xerces.xni.XMLString data,
                                  org.apache.xerces.xni.Augmentations augs)

Processing instruction.

Specified by:

processingInstruction in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

processingInstruction in class DefaultFilter

doctypeDecl

public void doctypeDecl(java.lang.String root,
                        java.lang.String pubid,
                        java.lang.String sysid,
                        org.apache.xerces.xni.Augmentations augs)

Doctype declaration.

Specified by:

doctypeDecl in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

doctypeDecl in class DefaultFilter

startElement

public void startElement(org.apache.xerces.xni.QName element,
                         org.apache.xerces.xni.XMLAttributes attrs,
                         org.apache.xerces.xni.Augmentations augs)

Start element.

Specified by:

startElement in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

startElement in class DefaultFilter

emptyElement

public void emptyElement(org.apache.xerces.xni.QName element,
                         org.apache.xerces.xni.XMLAttributes attrs,
                         org.apache.xerces.xni.Augmentations augs)

Empty element.

Specified by:

emptyElement in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

emptyElement in class DefaultFilter

startCDATA

public void startCDATA(org.apache.xerces.xni.Augmentations augs)

Start CDATA section.

Specified by:

startCDATA in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

startCDATA in class DefaultFilter

endCDATA

public void endCDATA(org.apache.xerces.xni.Augmentations augs)

End CDATA section.

Specified by:

endCDATA in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

endCDATA in class DefaultFilter

characters

public void characters(org.apache.xerces.xni.XMLString text,
                       org.apache.xerces.xni.Augmentations augs)

Characters.

Specified by:

characters in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

characters in class DefaultFilter

endElement

public void endElement(org.apache.xerces.xni.QName element,
                       org.apache.xerces.xni.Augmentations augs)

End element.

Specified by:

endElement in interface org.apache.xerces.xni.XMLDocumentHandler

Overrides:

endElement in class DefaultFilter

handleStartDocument

protected void handleStartDocument()

Handle start document.

handleStartElement

protected void handleStartElement(org.apache.xerces.xni.QName element,
                                  org.apache.xerces.xni.XMLAttributes attrs)

Handle start element.

synthesizeBinding

protected void synthesizeBinding(org.apache.xerces.xni.XMLAttributes attrs,
                                 java.lang.String ns)

Synthesize namespace binding.

synthesizedAugs

protected final org.apache.xerces.xni.Augmentations synthesizedAugs()

Returns an augmentations object with a synthesized item added.

purifyQName

protected org.apache.xerces.xni.QName purifyQName(org.apache.xerces.xni.QName qname)

Purify qualified name.

purifyName

protected java.lang.String purifyName(java.lang.String name,
                                      boolean localpart)

Purify name.

purifyText

protected org.apache.xerces.xni.XMLString purifyText(org.apache.xerces.xni.XMLString text)

Purify content.

toHexString

protected static java.lang.String toHexString(int c,
                                              int padlen)

Returns a padded hexadecimal string for the given value.