gnu.xml.aelfred2
Class XmlReader

java.lang.Object
  |
  +--gnu.xml.aelfred2.XmlReader

All Implemented Interfaces:

XMLReader

public final class XmlReader

extends java.lang.Object

implements XMLReader

This SAX2 parser optionally layers a validator over the Ælfred2 SAX2 parser. While this will not evaluate every XML validity constraint, it does support all the validity constraints that are of any real utility outside the strict SGML-compatible world. See the documentation for the SAXDriver class for information about the SAX2 features and properties that are supported, and documentation for the ValidationConsumer for information about what validity constraints may not be supported. (Ælfred2 tests some of those, even in non-validating mode, to achieve better conformance.)

Note that due to its internal construction, you can't change most handlers until parse() returns. This diverges slightly from SAX, which expects later binding to be supported. Early binding involves less runtime overhead, which is an issue for event pipelines as used inside this parser. Rather than relying on the parser to handle late binding to your own handlers, do it yourself.

Version:

$Date: 2001/07/10 23:00:00 $

Author:

David Brownell

See Also:

SAXDriver, ValidationConsumer

Constructor Summary

XmlReader()
Constructs a SAX Parser.

XmlReader(boolean invalidIsFatal)
Constructs a SAX Parser, optionally treating validity errors as if they were fatal errors.

Method Summary

ContentHandler	getContentHandler() SAX2: Returns the object used to report the logical content of an XML document.
DTDHandler	getDTDHandler() SAX2: Returns the object used to process declarations related to notations and unparsed entities.
EntityResolver	getEntityResolver() SAX2: Returns the object used when resolving external entities during parsing (both general and parameter entities).
ErrorHandler	getErrorHandler() SAX2: Returns the object used to receive callbacks for XML errors of all levels (fatal, nonfatal, warning); this is never null;
boolean	getFeature(java.lang.String featureId) SAX2: Tells whether this parser supports the specified feature.
java.lang.Object	getProperty(java.lang.String propertyId) SAX2: Returns the specified property.
void	parse(InputSource source) SAX1: Auxiliary API to parse an XML document, used mostly when no URI is available.
void	parse(java.lang.String systemId) SAX1: Preferred API to parse an XML document, using a system identifier (URI).
void	setContentHandler(ContentHandler handler) SAX2: Assigns the object used to report the logical content of an XML document.
void	setDTDHandler(DTDHandler handler) SAX1 Assigns DTD handler
void	setEntityResolver(EntityResolver handler) SAX1 Assigns parser's entity resolver
void	setErrorHandler(ErrorHandler handler) SAX1 Assigns error handler
void	setFeature(java.lang.String featureId, boolean state) SAX2: Sets the state of features supported in this parser.
void	setLocale(java.util.Locale locale) SAX1: Sets the locale used for diagnostics; currently, only locales using the English language are supported.
void	setProperty(java.lang.String propertyId, java.lang.Object value) SAX2: Assigns the specified property.

Methods inherited from class java.lang.Object

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

Constructor Detail

XmlReader

public XmlReader()

Constructs a SAX Parser.

XmlReader

public XmlReader(boolean invalidIsFatal)

Constructs a SAX Parser, optionally treating validity errors as if they were fatal errors.

Method Detail

getContentHandler

public ContentHandler getContentHandler()

SAX2: Returns the object used to report the logical content of an XML document.

Specified by:

getContentHandler in interface XMLReader

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

Returns:

The current content handler, or null if none has been registered.

See Also:

XMLReader.setContentHandler(org.xml.sax.ContentHandler)

setContentHandler

public void setContentHandler(ContentHandler handler)

SAX2: Assigns the object used to report the logical content of an XML document.

Specified by:

setContentHandler in interface XMLReader

Throws:

IllegalStateException - if called mid-parse

getDTDHandler

public DTDHandler getDTDHandler()

SAX2: Returns the object used to process declarations related to notations and unparsed entities.

Specified by:

getDTDHandler in interface XMLReader

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

Returns:

The current DTD handler, or null if none has been registered.

See Also:

XMLReader.setDTDHandler(org.xml.sax.DTDHandler)

setDTDHandler

public void setDTDHandler(DTDHandler handler)

SAX1 Assigns DTD handler

Specified by:

setDTDHandler in interface XMLReader

Throws:

IllegalStateException - if called mid-parse

getEntityResolver

public EntityResolver getEntityResolver()

SAX2: Returns the object used when resolving external entities during parsing (both general and parameter entities).

Specified by:

getEntityResolver in interface XMLReader

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

Returns:

The current entity resolver, or null if none has been registered.

See Also:

XMLReader.setEntityResolver(org.xml.sax.EntityResolver)

setEntityResolver

public void setEntityResolver(EntityResolver handler)

SAX1 Assigns parser's entity resolver

Specified by:

setEntityResolver in interface XMLReader

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

Parameters:

resolver - The entity resolver.

Throws:

java.lang.NullPointerException - If the resolver argument is null.

See Also:

XMLReader.getEntityResolver()

getErrorHandler

public ErrorHandler getErrorHandler()

SAX2: Returns the object used to receive callbacks for XML errors of all levels (fatal, nonfatal, warning); this is never null;

Specified by:

getErrorHandler in interface XMLReader

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

Returns:

The current error handler, or null if none has been registered.

See Also:

XMLReader.setErrorHandler(org.xml.sax.ErrorHandler)

setErrorHandler

public void setErrorHandler(ErrorHandler handler)

SAX1 Assigns error handler

Specified by:

setErrorHandler in interface XMLReader

Throws:

IllegalStateException - if called mid-parse

setProperty

public void setProperty(java.lang.String propertyId,
                        java.lang.Object value)
                 throws SAXNotRecognizedException,
                        SAXNotSupportedException

SAX2: Assigns the specified property.

Specified by:

setProperty in interface XMLReader

Throws:

IllegalStateException - if called mid-parse

getProperty

public java.lang.Object getProperty(java.lang.String propertyId)
                             throws SAXNotRecognizedException

SAX2: Returns the specified property.

Specified by:

getProperty in interface XMLReader

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

Parameters:

name - The property name, which is a fully-qualified URI.

Returns:

The current value of the property.

Throws:

SAXNotRecognizedException - When the XMLReader does not recognize the property name.

SAXNotSupportedException - When the XMLReader recognizes the property name but cannot determine its value at this time.

See Also:

XMLReader.setProperty(java.lang.String, java.lang.Object)

setFeature

public void setFeature(java.lang.String featureId,
                       boolean state)
                throws SAXNotRecognizedException,
                       SAXNotSupportedException

SAX2: Sets the state of features supported in this parser. Note that this parser requires reporting of namespace prefixes when validating.

Specified by:

setFeature in interface XMLReader

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

Parameters:

name - The feature name, which is a fully-qualified URI.

state - The requested state of the feature (true or false).

Throws:

SAXNotRecognizedException - When the XMLReader does not recognize the feature name.

SAXNotSupportedException - When the XMLReader recognizes the feature name but cannot set the requested value.

See Also:

XMLReader.getFeature(java.lang.String)

getFeature

public boolean getFeature(java.lang.String featureId)
                   throws SAXNotRecognizedException

SAX2: Tells whether this parser supports the specified feature. At this time, this directly parallels the underlying SAXDriver, except that validation is optionally supported.

Specified by:

getFeature in interface XMLReader

See Also:

SAXDriver

setLocale

public void setLocale(java.util.Locale locale)
               throws SAXException

SAX1: Sets the locale used for diagnostics; currently, only locales using the English language are supported.

Parameters:

locale - The locale for which diagnostics will be generated

parse

public void parse(java.lang.String systemId)
           throws SAXException,
                  java.io.IOException

SAX1: Preferred API to parse an XML document, using a system identifier (URI).

Specified by:

parse in interface XMLReader

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

Parameters:

systemId - The system identifier (URI).

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

java.io.IOException - An IO exception from the parser, possibly from a byte stream or character stream supplied by the application.

See Also:

XMLReader.parse(org.xml.sax.InputSource)

parse

public void parse(InputSource source)
           throws SAXException,
                  java.io.IOException

SAX1: Auxiliary API to parse an XML document, used mostly when no URI is available.

Specified by:

parse in interface XMLReader

Parameters:

source - The XML input source.

Throws:

IllegalStateException - if called mid-parse

SAXException - The handlers may throw any SAXException, and the parser normally throws SAXParseException objects.

java.io.IOException - IOExceptions are normally through through the parser if there are problems reading the source document.