arabica/SAX/helpers/DefaultHandler.h
2002-06-21 11:16:28 +00:00

369 lines
13 KiB
C++

#ifndef DEFAULTHANDLER_H
#define DEFAULTHANDLER_H
// DefaultHandler.h
// $Id$
#include <string>
#include <SAX/EntityResolver.h>
#include <SAX/DTDHandler.h>
#include <SAX/ContentHandler.h>
#include <SAX/ErrorHandler.h>
#include <SAX/Locator.h>
#include <SAX/Attributes.h>
#include <SAX/SAXException.h>
namespace SAX {
/**
* Default base class for SAX2 event handlers.
*
* <p>This class is available as a convenience base class for SAX2
* applications: it provides default implementations for all of the
* callbacks in the four core SAX2 handler classes:</p>
*
* <ul>
* <li>{@link basic_EntityResolver EntityResolver}</li>
* <li>{@link basic_DTDHandler DTDHandler}</li>
* <li>{@link basic_ContentHandler ContentHandler}</li>
* <li>{@link ErrorHandler ErrorHandler}</li>
* </ul>
*
* <p>Application writers can extend this class when they need to
* implement only part of an interface; parser writers can
* instantiate this class to provide default handlers when the
* application has not supplied its own.</p>
*
* <p>This class replaces the deprecated SAX1
* {@link basic_HandlerBase HandlerBase} class.</p>
*
* @since SAX 2.0
* @author Jez Higgins,
* <a href="mailto:jez@jezuk.co.uk">jez@jezuk.co.uk</a>
* @version 2.0
* @see basic_EntityResolver
* @see basic_DTDHandler
* @see basic_ContentHandler
* @see ErrorHandler
*/
template<class string_type>
class basic_DefaultHandler : public basic_EntityResolver<string_type>,
public basic_DTDHandler<string_type>,
public basic_ContentHandler<string_type>,
public ErrorHandler
{
public:
typedef string_type stringT;
typedef basic_InputSource<stringT> InputSourceT;
typedef basic_Locator<stringT> LocatorT;
typedef basic_Attributes<stringT> AttributesT;
basic_DefaultHandler() { }
virtual ~basic_DefaultHandler() { }
//////////////////////////////////////////////
// EntityResolver
/**
* Resolve an external entity.
*
* <p>Always return null, so that the parser will use the system
* identifier provided in the XML document. This method implements
* the SAX default behaviour: application writers can override it
* in a subclass to do special translations such as catalog lookups
* or URI redirection.</p>
*
* @param publicId The public identifer, or null if none is
* available.
* @param systemId The system identifier provided in the XML
* document.
* @return The new input source, (empty to require the
* default behaviour).
* @exception SAXException Any SAX exception.
* @see basic_EntityResolver#resolveEntity
*/
virtual InputSourceT resolveEntity(const stringT& publicId, const stringT& systemId)
{
return InputSourceT();
} // resolveEntity
//////////////////////////////////////////////
// DTDHandler
/**
* Receive notification of a notation declaration.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass if they wish to keep track of the notations
* declared in a document.</p>
*
* @param name The notation name.
* @param publicId The notation public identifier, or null if not
* available.
* @param systemId The notation system identifier.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_DTDHandler#notationDecl
*/
virtual void notationDecl(const stringT& name,
const stringT& publicId,
const stringT& systemId)
{
} // notationDecl
/**
* Receive notification of an unparsed entity declaration.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to keep track of the unparsed entities
* declared in a document.</p>
*
* @param name The entity name.
* @param publicId The entity public identifier, or null if not
* available.
* @param systemId The entity system identifier.
* @param notationName The name of the associated notation.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_DTDHandler#unparsedEntityDecl
*/
virtual void unparsedEntityDecl(const stringT& name,
const stringT& publicId,
const stringT& systemId,
const stringT& notationName)
{
} // unparsedEntityDecl
////////////////////////////////////////////////////
// ContentHandler
/**
* Receive a Locator object for document events.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass if they wish to store the locator for use
* with other document events.</p>
*
* @param locator A locator for all SAX document events.
* @see basic_ContentHandler#setDocumentLocator
* @see basic_Locator
*/
virtual void setDocumentLocator(const LocatorT& locator) { }
/**
* Receive notification of the beginning of the document.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the beginning
* of a document (such as allocating the root node of a tree or
* creating an output file).</p>
*
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#startDocument
*/
virtual void startDocument() { }
/**
* Receive notification of the end of the document.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the end
* of a document (such as finalising a tree or closing an output
* file).</p>
*
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#endDocument
*/
virtual void endDocument() { }
/**
* Receive notification of the start of a Namespace mapping.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the start of
* each Namespace prefix scope (such as storing the prefix mapping).</p>
*
* @param prefix The Namespace prefix being declared.
* @param uri The Namespace URI mapped to the prefix.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#startPrefixMapping
*/
virtual void startPrefixMapping(const stringT& prefix, const stringT& uri) { }
/**
* Receive notification of the end of a Namespace mapping.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the end of
* each prefix mapping.</p>
*
* @param prefix The Namespace prefix being declared.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#endPrefixMapping
*/
virtual void endPrefixMapping(const stringT& prefix) { }
/**
* Receive notification of the start of an element.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the start of
* each element (such as allocating a new tree node or writing
* output to a file).</p>
*
* @param name The element type name.
* @param attributes The specified or defaulted attributes.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#startElement
*/
virtual void startElement(const stringT& namespaceURI, const stringT& localName,
const stringT& qName, const AttributesT& atts) { }
/**
* Receive notification of the end of an element.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions at the end of
* each element (such as finalising a tree node or writing
* output to a file).</p>
*
* @param name The element type name.
* @param attributes The specified or defaulted attributes.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#endElement
*/
virtual void endElement(const stringT& namespaceURI, const stringT& localName,
const stringT& qName) { }
/**
* Receive notification of character data inside an element.
*
* <p>By default, do nothing. Application writers may override this
* method to take specific actions for each chunk of character data
* (such as adding the data to a node or buffer, or printing it to
* a file).</p>
*
* @param ch The characters.
* @param start The start position in the character array.
* @param length The number of characters to use from the
* character array.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#characters
*/
virtual void characters(const stringT& ch) { }
/**
* Receive notification of ignorable whitespace in element content.
*
* <p>By default, do nothing. Application writers may override this
* method to take specific actions for each chunk of ignorable
* whitespace (such as adding data to a node or buffer, or printing
* it to a file).</p>
*
* @param ch The whitespace characters.
* @param start The start position in the character array.
* @param length The number of characters to use from the
* character array.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#ignorableWhitespace
*/
virtual void ignorableWhitespace(const stringT& ch) { }
/**
* Receive notification of a processing instruction.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions for each
* processing instruction, such as setting status variables or
* invoking other methods.</p>
*
* @param target The processing instruction target.
* @param data The processing instruction data, or null if
* none is supplied.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#processingInstruction
*/
virtual void processingInstruction(const stringT& target, const stringT& data) { }
/**
* Receive notification of a skipped entity.
*
* <p>By default, do nothing. Application writers may override this
* method in a subclass to take specific actions for each
* processing instruction, such as setting status variables or
* invoking other methods.</p>
*
* @param name The name of the skipped entity.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see basic_ContentHandler#processingInstruction
*/
virtual void skippedEntity(const stringT& name) { }
/////////////////////////////////////////////////////
// ErrorHandler
/**
* Receive notification of a parser warning.
*
* <p>The default implementation does nothing. Application writers
* may override this method in a subclass to take specific actions
* for each warning, such as inserting the message in a log file or
* printing it to the console.</p>
*
* @param e The warning information encoded as an exception.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see ErrorHandler#warning
* @see SAXParseException
*/
virtual void warning(const SAXException&) { }
/**
* Receive notification of a recoverable parser error.
*
* <p>The default implementation does nothing. Application writers
* may override this method in a subclass to take specific actions
* for each error, such as inserting the message in a log file or
* printing it to the console.</p>
*
* @param e The warning information encoded as an exception.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see ErrorHandler#warning
* @see SAXParseException
*/
virtual void error(const SAXException&) { }
/**
* Report a fatal XML parsing error.
*
* <p>The default implementation throws a SAXParseException.
* Application writers may override this method in a subclass if
* they need to take specific actions for each fatal error (such as
* collecting all of the errors into a single report): in any case,
* the application must stop all regular processing when this
* method is invoked, since the document is no longer reliable, and
* the parser may no longer report parsing events.</p>
*
* @param e The error information encoded as an exception.
* @exception SAXException Any SAX exception, possibly
* wrapping another exception.
* @see ErrorHandler#fatalError
* @see SAXParseException
*/
virtual void fatalError(const SAXException& ex)
{
} // fatalError
private:
basic_DefaultHandler(const basic_DefaultHandler&);
basic_DefaultHandler& operator=(const basic_DefaultHandler&);
bool operator==(const basic_DefaultHandler&);
}; // class basic_DefaultHandler
typedef basic_DefaultHandler<std::string> DefaultHandler;
typedef basic_DefaultHandler<std::wstring> wDefaultHandler;
} // namespace SAX
#endif