com.sapportals.wcm.util.html

Interface IHTMLReader

All Known Subinterfaces:

IHTMLFilter

All Known Implementing Classes:

HTMLFilterImpl

public interface IHTMLReader

Reads HTML documents and generates events.

The IHTMLReader generates events for HTML documents. Events are sent to the IHTMLContentHandler. There can be only one content handler per reader.

A document is parsed by first setting the input source and then calling parse() once or parseNextEvent() repeatedly. parseNextEvent() parses the document until the next event was sent to the content handler and then returns to the caller. It is not garantueed that exactly one event is generated.

Input Sources and Encodings:

• When a Reader is used as input source, no attempt is made to detect the encoding of the html document. getEncoding() will return null in that case.
• When a InputStream together with an encoding is used, any encoding specified in meta tags of the document is ignored and the given encoding is used.
• When a InputStream together without encoding is used, the reader will look into the first n octets of the html document to detect a HTML meta tag with Content-Type which specifies the character set to use. If no encoding is found, ISO-8859-1 is assumed. The number of octets used for encoding detection is implementation defined.

Note that implementations of this class are not multithread-safe .

Copyright (c) SAP AG 2001-2002

Method Summary

void	discard() Free all allocated resources.
IHTMLContentHandler	getContentHandler() Get the registered content handler.
String	getEncoding() Return the encoding used in the document.
ITextContentHandler	getRawContentHandler() Get the registered raw content handler.
void	parse() Parse the complete document, generating events, until the source is read emtpy.
boolean	parseNextEvent() Parse the document, generating an events, and return to the caller.
void	setContentHandler(IHTMLContentHandler handler) Set the content handler to a new value.
void	setRawContentHandler(ITextContentHandler handler) Set the content handler to a new value.
void	setSource(InputStream input) Set InputStream as document source.
void	setSource(InputStream input, String encoding) Set InputStream as document source, use the given encoding.
void	setSource(Reader input) Set Reader as document source, encoding is irrelevant.

Method Detail

getContentHandler

public IHTMLContentHandler getContentHandler()

Get the registered content handler. Returns null if none is installed.

Returns:

registered content handler

getRawContentHandler

public ITextContentHandler getRawContentHandler()

Get the registered raw content handler. Returns null if none is installed.

Returns:

registered content handler

setContentHandler

public void setContentHandler(IHTMLContentHandler handler)

Set the content handler to a new value. null is allowed to deregister an installed handler.

Parameters:

handler - to register

setRawContentHandler

public void setRawContentHandler(ITextContentHandler handler)

Set the content handler to a new value. null is allowed to deregister an installed handler.

Parameters:

handler - to register

getEncoding

public String getEncoding()
                   throws HTMLException,
                          IOException

Return the encoding used in the document.

Returns:

encoding used in document or null if unknown.

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

setSource

public void setSource(InputStream input)
               throws HTMLException,
                      IOException

Set InputStream as document source. Encoding will be detected.

Parameters:

input - stream to read document from

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

setSource

public void setSource(InputStream input,
                      String encoding)
               throws HTMLException,
                      IOException

Set InputStream as document source, use the given encoding.

Parameters:

input - stream to read document from

encoding - to use for stream

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

setSource

public void setSource(Reader input)
               throws HTMLException,
                      IOException

Set Reader as document source, encoding is irrelevant.

Parameters:

input - to read document from

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

parse

public void parse()
           throws HTMLException,
                  IOException

Parse the complete document, generating events, until the source is read emtpy.

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

parseNextEvent

public boolean parseNextEvent()
                       throws HTMLException,
                              IOException

Parse the document, generating an events, and return to the caller. Will return true as long as there are more events to read.

Returns:

if there are more events to read

Throws:

HTMLException - when document is not legal HTML

IOException - on read errors

discard

public void discard()

Free all allocated resources. Not necessary to call when parsing has finished.