mirror of
https://github.com/jezhiggins/arabica
synced 2024-12-28 22:23:21 +01:00
115 lines
3.9 KiB
C++
115 lines
3.9 KiB
C++
#ifndef EntityResolverH
|
|
#define EntityResolverH
|
|
|
|
// EntityResolver.h
|
|
// $Id$
|
|
|
|
#include <string>
|
|
#include <SAX/InputSource.h>
|
|
|
|
namespace SAX
|
|
{
|
|
|
|
/**
|
|
* Basic interface for resolving entities.
|
|
*
|
|
* <p>If a SAX application needs to implement customized handling
|
|
* for external entities, it must implement this interface and
|
|
* register an instance with the SAX driver using the
|
|
* {@link basic_XMLReader#setEntityResolver setEntityResolver}
|
|
* method.</p>
|
|
*
|
|
* <p>The XML reader will then allow the application to intercept any
|
|
* external entities (including the external DTD subset and external
|
|
* parameter entities, if any) before including them.</p>
|
|
*
|
|
* <p>Many SAX applications will not need to implement this interface,
|
|
* but it will be especially useful for applications that build
|
|
* XML documents from databases or other specialised input sources,
|
|
* or for applications that use URI types other than URLs.</p>
|
|
*
|
|
* <p>The following resolver would provide the application
|
|
* with a special character stream for the entity with the system
|
|
* identifier "http://www.myhost.com/today":</p>
|
|
*
|
|
* <pre>
|
|
* #include <EntityResolver>
|
|
* #include <InputSource>
|
|
*
|
|
* public class MyResolver implements SAX::EntityResolver
|
|
* {
|
|
* public InputSource resolveEntity (const std::string& publicId, const std::string& systemId)
|
|
* {
|
|
* if(systemId == "http://www.myhost.com/today")
|
|
* {
|
|
* // return a special input source
|
|
* MyReader reader = new MyReader();
|
|
* return SAX::InputSource(reader);
|
|
* } else {
|
|
* // request default behaviour
|
|
* return SAX::InputSource();
|
|
* }
|
|
* }
|
|
* }
|
|
* </pre>
|
|
*
|
|
* <p>The application can also use this interface to redirect system
|
|
* identifiers to local URIs or to look up replacements in a catalog
|
|
* (possibly by using the public identifier).</p>
|
|
*
|
|
* @since SAX 1.0
|
|
* @author Jez Higgins,
|
|
* <a href="mailto:jez@jezuk.co.uk">jez@jezuk.co.uk</a>
|
|
* @version 2.0
|
|
* @see basic_Parser#setEntityResolver
|
|
* @see basic_InputSource
|
|
*/
|
|
template<class string_type>
|
|
class basic_EntityResolver
|
|
{
|
|
public:
|
|
typedef string_type stringT;
|
|
typedef basic_InputSource<stringT> InputSourceT;
|
|
|
|
virtual ~basic_EntityResolver() { };
|
|
|
|
/**
|
|
* Allow the application to resolve external entities.
|
|
*
|
|
* <p>The Parser will call this method before opening any external
|
|
* entity except the top-level document entity (including the
|
|
* external DTD subset, external entities referenced within the
|
|
* DTD, and external entities referenced within the document
|
|
* element): the application may request that the parser resolve
|
|
* the entity itself, that it use an alternative URI, or that it
|
|
* use an entirely different input source.</p>
|
|
*
|
|
* <p>Application writers can use this method to redirect external
|
|
* system identifiers to secure and/or local URIs, to look up
|
|
* public identifiers in a catalogue, or to read an entity from a
|
|
* database or other input source (including, for example, a dialog
|
|
* box).</p>
|
|
*
|
|
* <p>If the system identifier is a URL, the SAX parser must
|
|
* resolve it fully before reporting it to the application.</p>
|
|
*
|
|
* @param publicId The public identifier of the external entity
|
|
* being referenced, or null if none was supplied.
|
|
* @param systemId The system identifier of the external entity
|
|
* being referenced.
|
|
* @return An InputSource object describing the new input source,
|
|
* or null to request that the parser open a regular
|
|
* URI connection to the system identifier.
|
|
* @exception SAXException Any SAX exception.
|
|
* @see basic_InputSource
|
|
*/
|
|
virtual InputSourceT resolveEntity(const stringT& publicId, const stringT& systemId) = 0;
|
|
}; // class EntityResolver
|
|
|
|
typedef basic_EntityResolver<std::string> EntityResolver;
|
|
typedef basic_EntityResolver<std::wstring> wEntityResolver;
|
|
|
|
}; // namespace SAX
|
|
|
|
#endif
|
|
// end of file
|