poco/XML/include/Poco/SAX/XMLReader.h
Guenter Obiltschnig 2d4078f392 submitted 1.2.0
2006-08-29 07:10:35 +00:00

224 lines
9.8 KiB
C++

//
// XMLReader.h
//
// $Id: //poco/1.2/XML/include/Poco/SAX/XMLReader.h#1 $
//
// Library: XML
// Package: SAX
// Module: SAX
//
// SAX2 XMLReader Interface.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
//
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
#ifndef SAX_XMLReader_INCLUDED
#define SAX_XMLReader_INCLUDED
#include "Poco/XML/XML.h"
#include "Poco/XML/XMLString.h"
namespace Poco {
namespace XML {
class EntityResolver;
class DTDHandler;
class ContentHandler;
class ErrorHandler;
class InputSource;
class LexicalHandler;
class NamespaceHandler;
class XML_API XMLReader
/// Interface for reading an XML document using callbacks.
/// XMLReader is the interface that an XML parser's SAX2 driver must
/// implement. This interface allows an application to set and
/// query features and properties in the parser, to register event handlers
/// for document processing, and to initiate a document parse.
/// All SAX interfaces are assumed to be synchronous: the parse methods must not
/// return until parsing is complete, and readers
/// must wait for an event-handler callback to return before reporting the next event.
{
public:
virtual void setEntityResolver(EntityResolver* pResolver) = 0;
/// Allow an application to register an entity resolver.
///
/// If the application does not register an entity resolver, the
/// XMLReader will perform its own default resolution.
///
/// Applications may register a new or different resolver in the middle of a
/// parse, and the SAX parser must begin using the new resolver immediately.
virtual EntityResolver* getEntityResolver() const = 0;
/// Return the current entity resolver.
virtual void setDTDHandler(DTDHandler* pDTDHandler) = 0;
/// Allow an application to register a DTD event handler.
///
/// If the application does not register a DTD handler, all DTD events reported by
/// the SAX parser will be silently ignored.
///
/// Applications may register a new or different handler in the middle of a parse,
/// and the SAX parser must begin using the new handler immediately.
virtual DTDHandler* getDTDHandler() const = 0;
/// Return the current DTD handler.
virtual void setContentHandler(ContentHandler* pContentHandler) = 0;
/// Allow an application to register a content event handler.
///
/// If the application does not register a content handler, all content events
/// reported by the SAX parser will be silently ignored.
///
/// Applications may register a new or different handler in the middle of a parse,
/// and the SAX parser must begin using the new handler immediately.
virtual ContentHandler* getContentHandler() const = 0;
/// Return the current content handler.
virtual void setErrorHandler(ErrorHandler* pErrorHandler) = 0;
/// Allow an application to register an error event handler.
///
/// If the application does not register an error handler, all error events reported by
/// the SAX parser will be silently ignored; however, normal processing may not continue.
/// It is highly recommended that all SAX applications implement an error handler to avoid
/// unexpected bugs.
///
/// Applications may register a new or different handler in the middle of a parse, and the
/// SAX parser must begin using the new handler immediately.
virtual ErrorHandler* getErrorHandler() const = 0;
/// Return the current error handler.
virtual void setFeature(const XMLString& featureId, bool state) = 0;
/// Set the state of a feature.
///
/// The feature name is any fully-qualified URI. It is possible for an XMLReader to
/// expose a feature value but to be unable to change the current value. Some feature
/// values may be immutable or mutable only in specific contexts, such as before, during,
/// or after a parse.
///
/// All XMLReaders are required to support setting http://xml.org/sax/features/namespaces
/// to true and http://xml.org/sax/features/namespace-prefixes to false.
virtual bool getFeature(const XMLString& featureId) const = 0;
/// Look up the value of a feature.
///
/// The feature name is any fully-qualified URI. It is possible for an XMLReader
/// to recognize a feature name but temporarily be unable to return its value.
/// Some feature values may be available only in specific contexts, such as before,
/// during, or after a parse. Also, some feature values may not be programmatically
/// accessible. (In the case of an adapter for SAX1 Parser, there is no
/// implementation-independent way to expose whether the underlying parser is performing
/// validation, expanding external entities, and so forth.)
///
/// All XMLReaders are required to recognize the
/// http://xml.org/sax/features/namespaces and the
/// http://xml.org/sax/features/namespace-prefixes feature names.
/// Implementors are free (and encouraged) to invent their own features,
/// using names built on their own URIs.
virtual void setProperty(const XMLString& propertyId, const XMLString& value) = 0;
/// Set the value of a property.
///
/// The property name is any fully-qualified URI. It is possible for an XMLReader
/// to recognize a property name but to be unable to change the current value.
/// Some property values may be immutable or mutable only in specific contexts,
/// such as before, during, or after a parse.
///
/// XMLReaders are not required to recognize setting any specific property names, though a
/// core set is defined by SAX2.
///
/// This method is also the standard mechanism for setting extended handlers.
virtual void setProperty(const XMLString& propertyId, void* value) = 0;
/// Set the value of a property.
/// See also setProperty(const XMLString&, const XMLString&).
virtual void* getProperty(const XMLString& propertyId) const = 0;
/// Look up the value of a property.
/// String values are returned as XMLChar*
/// The property name is any fully-qualified URI. It is possible for an XMLReader to
/// recognize a property name but temporarily be unable to return its value. Some property
/// values may be available only in specific contexts, such as before, during, or after a parse.
///
/// XMLReaders are not required to recognize any specific property names, though an initial
/// core set is documented for SAX2.
///
/// Implementors are free (and encouraged) to invent their own properties, using names
/// built on their own URIs.
virtual void parse(InputSource* pSource) = 0;
/// Parse an XML document.
///
/// The application can use this method to instruct the XML reader to begin parsing an
/// XML document from any valid input source (a character stream, a byte stream, or a URI).
///
/// Applications may not invoke this method while a parse is in progress (they should create
/// a new XMLReader instead for each nested XML document). Once a parse is complete, an
/// application may reuse the same XMLReader object, possibly with a different input source.
/// Configuration of the XMLReader object (such as handler bindings and values established for
/// feature flags and properties) is unchanged by completion of a parse, unless the definition of that
/// aspect of the configuration explicitly specifies other behavior. (For example, feature flags or
/// properties exposing characteristics of the document being parsed.)
///
/// During the parse, the XMLReader will provide information about the XML document through the registered
/// event handlers.
///
/// This method is synchronous: it will not return until parsing has ended. If a client application
/// wants to terminate parsing early, it should throw an exception.
virtual void parse(const XMLString& systemId) = 0;
/// Parse an XML document from a system identifier.
/// See also parse(InputSource*).
// SAX Features
static const XMLString FEATURE_VALIDATION;
static const XMLString FEATURE_NAMESPACES;
static const XMLString FEATURE_NAMESPACE_PREFIXES;
static const XMLString FEATURE_EXTERNAL_GENERAL_ENTITIES;
static const XMLString FEATURE_EXTERNAL_PARAMETER_ENTITIES;
static const XMLString FEATURE_STRING_INTERNING;
// SAX Properties
static const XMLString PROPERTY_DECLARATION_HANDLER;
static const XMLString PROPERTY_LEXICAL_HANDLER;
protected:
virtual ~XMLReader();
};
} } // namespace Poco::XML
#endif // SAX_XMLReader_INCLUDED