gnu.xml.pipeline
Class WellFormednessFilter

java.lang.Object
  |
  +--gnu.xml.pipeline.EventFilter
        |
        +--gnu.xml.pipeline.WellFormednessFilter

All Implemented Interfaces:

ContentHandler, DeclHandler, DTDHandler, EventConsumer, LexicalHandler

public final class WellFormednessFilter

extends EventFilter

This filter reports fatal exceptions in the case of event streams that are not well formed. The rules currently tested include:

• setDocumentLocator ... may be called only before startDocument
• startDocument/endDocument ... must be paired, and all other calls (except setDocumentLocator) must be nested within these.
• startElement/endElement ... must be correctly paired, and may never appear within CDATA sections.
• comment ... can't contain "--"
• character data ... can't contain "]]>"
• whitespace ... can't contain CR
• whitespace and character data must be within an element
• processing instruction ... can't contain "?>" or CR
• startCDATA/endCDATA ... must be correctly paired.

Other checks for event stream correctness may be provided in the future. For example, insisting that entity boundaries nest correctly, namespace scopes nest correctly, namespace values never contain relative URIs, attributes don't have "<" characters; and more.

Version:

$Date: 2001/07/10 22:56:33 $

Author:

David Brownell

Fields inherited from class gnu.xml.pipeline.EventFilter

DECL_HANDLER, FEATURE_URI, LEXICAL_HANDLER, PROPERTY_URI

Constructor Summary

WellFormednessFilter()
Swallows all events after performing well formedness checks.

WellFormednessFilter(EventConsumer consumer)
Passes events through to the specified consumer, after first processing them.

Method Summary

void	characters(char[] buf, int off, int len) SAX2: passes this callback to the next consumer, if any
void	comment(char[] buf, int off, int len) SAX2: passes this callback to the next consumer, if any
void	endCDATA() SAX2: passes this callback to the next consumer, if any
void	endDocument() SAX2: passes this callback to the next consumer, if any
void	endDTD() SAX2: passes this callback to the next consumer, if any
void	endElement(java.lang.String ns, java.lang.String l, java.lang.String name) SAX2: passes this callback to the next consumer, if any
void	ignorableWhitespace(char[] buf, int off, int len) SAX2: passes this callback to the next consumer, if any
void	notationDecl(java.lang.String name, java.lang.String pub, java.lang.String sys) SAX1: passes this callback to the next consumer, if any
void	processingInstruction(java.lang.String target, java.lang.String data) SAX2: passes this callback to the next consumer, if any
void	reset() Resets state as if any preceding event stream was well formed.
void	setDocumentLocator(Locator l) Throws an exception when called after startDocument.
void	startCDATA() SAX2: passes this callback to the next consumer, if any
void	startDocument() SAX2: passes this callback to the next consumer, if any
void	startDTD(java.lang.String root, java.lang.String p, java.lang.String s) SAX2: passes this callback to the next consumer, if any
void	startElement(java.lang.String ns, java.lang.String l, java.lang.String name, Attributes atts) SAX2: passes this callback to the next consumer, if any
void	unparsedEntityDecl(java.lang.String name, java.lang.String p, java.lang.String s, java.lang.String n) SAX1: passes this callback to the next consumer, if any

Methods inherited from class gnu.xml.pipeline.EventFilter

attributeDecl, bind, elementDecl, endEntity, endPrefixMapping, externalEntityDecl, getContentHandler, getDocumentLocator, getDTDHandler, getErrorHandler, getNext, getProperty, internalEntityDecl, setContentHandler, setDTDHandler, setErrorHandler, setProperty, skippedEntity, startEntity, startPrefixMapping

Methods inherited from class java.lang.Object

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

Constructor Detail

WellFormednessFilter

public WellFormednessFilter()

Swallows all events after performing well formedness checks.

WellFormednessFilter

public WellFormednessFilter(EventConsumer consumer)

Passes events through to the specified consumer, after first processing them.

Method Detail

reset

public void reset()

Resets state as if any preceding event stream was well formed. Particularly useful if it ended through some sort of error, and the endDocument call wasn't made.

setDocumentLocator

public void setDocumentLocator(Locator l)

Throws an exception when called after startDocument.

Overrides:

setDocumentLocator in class EventFilter

Parameters:

l - the locator, to be used in error reporting or relative URI resolution.

Throws:

IllegalStateException - when called after the document has already been started

startDocument

public void startDocument()
                   throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

startDocument in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

ContentHandler.endDocument()

startElement

public void startElement(java.lang.String ns,
                         java.lang.String l,
                         java.lang.String name,
                         Attributes atts)
                  throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

startElement in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Parameters:

uri - The Namespace URI, or the empty string if the element has no Namespace URI or if Namespace processing is not being performed.

localName - The local name (without prefix), or the empty string if Namespace processing is not being performed.

qName - The qualified name (with prefix), or the empty string if qualified names are not available.

atts - The attributes attached to the element. If there are no attributes, it shall be an empty Attributes object.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

ContentHandler.endElement(java.lang.String, java.lang.String, java.lang.String), Attributes

endElement

public void endElement(java.lang.String ns,
                       java.lang.String l,
                       java.lang.String name)
                throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

endElement in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Parameters:

uri - The Namespace URI, or the empty string if the element has no Namespace URI or if Namespace processing is not being performed.

localName - The local name (without prefix), or the empty string if Namespace processing is not being performed.

qName - The qualified XML 1.0 name (with prefix), or the empty string if qualified names are not available.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

endDocument

public void endDocument()
                 throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

endDocument in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

ContentHandler.startDocument()

startDTD

public void startDTD(java.lang.String root,
                     java.lang.String p,
                     java.lang.String s)
              throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

startDTD in class EventFilter

Following copied from interface: org.xml.sax.ext.LexicalHandler

Parameters:

name - The document type name.

publicId - The declared public identifier for the external DTD subset, or null if none was declared.

systemId - The declared system identifier for the external DTD subset, or null if none was declared.

Throws:

SAXException - The application may raise an exception.

See Also:

LexicalHandler.endDTD(), LexicalHandler.startEntity(java.lang.String)

notationDecl

public void notationDecl(java.lang.String name,
                         java.lang.String pub,
                         java.lang.String sys)
                  throws SAXException

Description copied from class: EventFilter

SAX1: passes this callback to the next consumer, if any

Overrides:

notationDecl in class EventFilter

Following copied from interface: org.xml.sax.DTDHandler

Parameters:

name - The notation name.

publicId - The notation's public identifier, or null if none was given.

systemId - The notation's system identifier, or null if none was given.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

DTDHandler.unparsedEntityDecl(java.lang.String, java.lang.String, java.lang.String, java.lang.String), AttributeList

unparsedEntityDecl

public void unparsedEntityDecl(java.lang.String name,
                               java.lang.String p,
                               java.lang.String s,
                               java.lang.String n)
                        throws SAXException

Description copied from class: EventFilter

SAX1: passes this callback to the next consumer, if any

Overrides:

unparsedEntityDecl in class EventFilter

Following copied from interface: org.xml.sax.DTDHandler

Parameters:

name - The unparsed entity's name.

publicId - The entity's public identifier, or null if none was given.

systemId - The entity's system identifier.

notation - name The name of the associated notation.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

DTDHandler.notationDecl(java.lang.String, java.lang.String, java.lang.String), AttributeList

endDTD

public void endDTD()
            throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

endDTD in class EventFilter

Following copied from interface: org.xml.sax.ext.LexicalHandler

Throws:

SAXException - The application may raise an exception.

See Also:

LexicalHandler.startDTD(java.lang.String, java.lang.String, java.lang.String)

characters

public void characters(char[] buf,
                       int off,
                       int len)
                throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

characters in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Parameters:

ch - The characters from the XML document.

start - The start position in the array.

length - The number of characters to read from the array.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

ContentHandler.ignorableWhitespace(char[], int, int), Locator

ignorableWhitespace

public void ignorableWhitespace(char[] buf,
                                int off,
                                int len)
                         throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

ignorableWhitespace in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Parameters:

ch - The characters from the XML document.

start - The start position in the array.

length - The number of characters to read from the array.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

ContentHandler.characters(char[], int, int)

processingInstruction

public void processingInstruction(java.lang.String target,
                                  java.lang.String data)
                           throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

processingInstruction in class EventFilter

Following copied from interface: org.xml.sax.ContentHandler

Parameters:

target - The processing instruction target.

data - The processing instruction data, or null if none was supplied. The data does not include any whitespace separating it from the target.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

comment

public void comment(char[] buf,
                    int off,
                    int len)
             throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

comment in class EventFilter

Following copied from interface: org.xml.sax.ext.LexicalHandler

Parameters:

ch - An array holding the characters in the comment.

start - The starting position in the array.

length - The number of characters to use from the array.

Throws:

SAXException - The application may raise an exception.

startCDATA

public void startCDATA()
                throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

startCDATA in class EventFilter

Following copied from interface: org.xml.sax.ext.LexicalHandler

Throws:

SAXException - The application may raise an exception.

See Also:

LexicalHandler.endCDATA()

endCDATA

public void endCDATA()
              throws SAXException

Description copied from class: EventFilter

SAX2: passes this callback to the next consumer, if any

Overrides:

endCDATA in class EventFilter

Following copied from interface: org.xml.sax.ext.LexicalHandler

Throws:

SAXException - The application may raise an exception.

See Also:

LexicalHandler.startCDATA()