Class Summary : TBufferedXMLReaderImpl

Buffered Base class for deriving an XML Reader.

Methods

procedure checkNotParsing(SAXString, SAXString)
procedure setColumnNumber(Integer)
procedure setLineNumber(Integer)
procedure setPublicId(PSAXChar)
procedure setSystemId(PSAXChar)
procedure parseInput(IInputSource)
function getFeature(SAXString) : Boolean
procedure setFeature(SAXString, Boolean)
function getProperty(SAXString) : IProperty
procedure setEntityResolver(IEntityResolver)
function getEntityResolver() : IEntityResolver
procedure setDTDHandler(IBufferedDTDHandler)
function getDTDHandler() : IBufferedDTDHandler
procedure setContentHandler(IBufferedContentHandler)
function getContentHandler() : IBufferedContentHandler
procedure setErrorHandler(IErrorHandler)
function getErrorHandler() : IErrorHandler
procedure parse(IInputSource)
procedure parse(SAXString)
function getPublicId() : PSAXChar
function getSystemId() : PSAXChar
function getLineNumber() : Integer
function getColumnNumber() : Integer

Properties



procedure checkNotParsing( propType : SAXString; name : SAXString);

Check if we are already parsing

Throw an exception if we are parsing. Use this method to detect illegal feature or property changes.


Parameter : propType A string value containing the type of property that cannot be changed while parsing.
Parameter : propTypeLength The length of the propTypeBuffer The value may be -1 which indicates that the buffer is null-terminated. If the value is 0 then the buffer may be nil.
Parameter : name A string value containing the name of the property that cannot be changed while parsing.
Parameter : nameLength The length of the nameBuffer The value may be -1 which indicates that the buffer is null-terminated. If the value is 0 then the buffer may be nil.

Top


procedure setColumnNumber( value : Integer);


Top


procedure setLineNumber( value : Integer);


Top


procedure setPublicId( value : PSAXChar);


Top


procedure setSystemId( value : PSAXChar);


Top


procedure parseInput(const input : IInputSource);


Top


function getFeature(const name : SAXString) : Boolean;

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 to be unable to return its value; this is especially true in the case of an adapter for a SAX1 Parser, which has no way of knowing whether the underlying parser is performing validation or expanding external entities.

All XMLReaders are required to recognize the http://xml.org/sax/features/namespaces and the http://xml.org/sax/features/namespace-prefixes feature names.

Some feature values may be available only in specific contexts, such as before, during, or after a parse.

Typical usage is something like this:

 var
   r : IXMLReader;
 begin
   r:= TMySAXDriver.Create() as IXMLReader;

   // try to activate validation
   try
     r.setFeature('http://xml.org/sax/features/validation', true);
   except
     on e : ESAXException do
     begin
       Showmessage('Cannot activate validation.');
     end;
   end;

   // register event handlers
   r.setContentHandler(TMyContentHandler.Create() as IContentHandler);
   r.setErrorHandler(TMyErrorHandler.Create() as IErrorHandler);

   // parse the first document
   try
     r.parse('file://c:/mydoc.xml');
   except
     on e : ESAXException do
     begin
       Showmessage('XML exception reading document.');
     end;
     on e : Exception do
     begin
       Showmessage('Exception reading document.');
     end;
   end;
 

Implementors are free (and encouraged) to invent their own features, using names built on their own URIs.


Parameter : name The feature name, which is a fully-qualified URI.
Result : The current state of the feature (true or false).
Exception : ESAXNotRecognizedException When the XMLReader does not recognize the feature name.
Exception : ESAXNotSupportedException When the XMLReader recognizes the feature name but cannot determine its value at this time.
See : TBufferedXMLReaderImpl.setFeature

Top


procedure setFeature(const name : SAXString; value : Boolean);

Set the state of a feature.

The feature name is any fully-qualified URI. It is possible for an XMLReader to recognize a feature name but to be unable to set its value; this is especially true in the case of an adapter for a SAX1 Parser, which has no way of affecting whether the underlying parser is validating, for example.

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.

Some feature values may be immutable or mutable only in specific contexts, such as before, during, or after a parse.


Parameter : name The feature name, which is a fully-qualified URI.
Parameter : state The requested state of the feature (true or false).
Exception : ESAXNotRecognizedException When the XMLReader does not recognize the feature name.
Exception : ESAXNotSupportedException When the XMLReader recognizes the feature name but cannot set the requested value.
See : TBufferedXMLReaderImpl.getFeature

Top


function getProperty(const name : SAXString) : IProperty;

Look up 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 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.

Within SAX for Pascal property setting is handled through the interface that is returned by the call to getProperty. This eliminates the need for multiple lookups in tight loop situations as a user can maintain a reference to the interface.


Parameter : name The property name, which is a fully-qualified URI.
Result : s An Interface that allows the getting and setting of the property
Exception : ESAXNotRecognizedException If the property interface cannot be retrieved.
Exception : ESAXNotSupportedException When the XMLReader recognizes the property name but cannot determine its interface value at this time.

Top


procedure setEntityResolver(const resolver : IEntityResolver);

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.


Parameter : resolver The entity resolver.
Exception : Exception If the resolver argument is nil.
See : TBufferedXMLReaderImpl.getEntityResolver

Top


function getEntityResolver() : IEntityResolver;

Return the current entity resolver.
Result : The current entity resolver, or nil if none has been registered.
See : TBufferedXMLReaderImpl.setEntityResolver

Top


procedure setDTDHandler(const handler : IBufferedDTDHandler);

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.


Parameter : handler The DTD handler.
Exception : Exception If the handler argument is nil.
See : TBufferedXMLReaderImpl.getDTDHandler

Top


function getDTDHandler() : IBufferedDTDHandler;

Return the current DTD handler.
Result : The current DTD handler, or nil if none has been registered.
See : TBufferedXMLReaderImpl.setDTDHandler

Top


procedure setContentHandler(const handler : IBufferedContentHandler);

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.


Parameter : handler The content handler.
Exception : Exception If the handler argument is nil.
See : TBufferedXMLReaderImpl.getContentHandler

Top


function getContentHandler() : IBufferedContentHandler;

Return the current content handler.
Result : The current content handler, or nil if none has been registered.
See : TBufferedXMLReaderImpl.setContentHandler

Top


procedure setErrorHandler(const handler : IErrorHandler);

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.


Parameter : handler The error handler.
Exception : Exception If the handler argument is nil.
See : TBufferedXMLReaderImpl.getErrorHandler

Top


function getErrorHandler() : IErrorHandler;

Return the current error handler.
Result : The current error handler, or nil if none has been registered.
See : TBufferedXMLReaderImpl.setErrorHandler

Top


procedure parse(const input : IInputSource);

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.

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.


Parameter : source The input source for the top-level of the XML document.
Exception : ESAXException Any SAX exception.
Exception : Exception An IO exception from the parser, possibly from a byte stream or character stream supplied by the application.
See : TInputSource
See : TBufferedXMLReaderImpl.parse(SAXString)
See : TBufferedXMLReaderImpl.setEntityResolver
See : TBufferedXMLReaderImpl.setDTDHandler
See : TBufferedXMLReaderImpl.setContentHandler
See : TBufferedXMLReaderImpl.setErrorHandler

Top


procedure parse(const systemId : SAXString);

Parse an XML document from a system identifier (URI).

This method is a shortcut for the common case of reading a document from a system identifier. It is the exact equivalent of the following:

 input:= TInputSource.Create(systemId);
 try
   parse(input);
 finally
   input.Free;
 end;
 

If the system identifier is a URL, it must be fully resolved by the application before it is passed to the parser.


Parameter : systemId The system identifier (URI).
Exception : ESAXException Any SAX exception.
Exception : Exception An IO exception from the parser, possibly from a byte stream or character stream supplied by the application.
See : TBufferedXMLReaderImpl.parse(TInputSource)

Top


function getPublicId() : PSAXChar;

Return the public identifier for the current document event.

The return value is the public identifier of the document entity or of the external parsed entity in which the markup triggering the event appears.


Result : A string containing the public identifier, or empty if none is available.
See : TBufferedXMLReaderImpl.getSystemId

Top


function getSystemId() : PSAXChar;

Return the system identifier for the current document event.

The return value is the system identifier of the document entity or of the external parsed entity in which the markup triggering the event appears.

If the system identifier is a URL, the parser must resolve it fully before passing it to the application.


Result : A string containing the system identifier, or empty if none is available.
See : TBufferedXMLReaderImpl.getPublicId

Top


function getLineNumber() : Integer;

Return the line number where the current document event ends.

Warning: The return value from the method is intended only as an approximation for the sake of error reporting; it is not intended to provide sufficient information to edit the character content of the original XML document.

The return value is an approximation of the line number in the document entity or external parsed entity where the markup triggering the event appears.

If possible, the SAX driver should provide the line position of the first character after the text associated with the document event. The first line in the document is line 1.


Result : The line number, or -1 if none is available.
See : TBufferedXMLReaderImpl.getColumnNumber

Top


function getColumnNumber() : Integer;

Return the column number where the current document event ends.

Warning: The return value from the method is intended only as an approximation for the sake of error reporting; it is not intended to provide sufficient information to edit the character content of the original XML document.

The return value is an approximation of the column number in the document entity or external parsed entity where the markup triggering the event appears.

If possible, the SAX driver should provide the line position of the first character after the text associated with the document event.

If possible, the SAX driver should provide the line position of the first character after the text associated with the document event. The first column in each line is column 1.


Result : The column number, or -1 if none is available.
See : TBufferedXMLReaderImpl.getLineNumber

Top


useNamespaces


property useNamespaces: Boolean read Fnamespaces write Fnamespaces

Top


usePrefixes


property usePrefixes: Boolean read Fprefixes write Fprefixes

Top