net.sf.fikin.xml.sax
Class BufferingPipe

java.lang.Object
  net.sf.fikin.xml.sax.PipeHandler
      net.sf.fikin.xml.sax.BufferingPipe

All Implemented Interfaces:

SAXHandler, org.xml.sax.ContentHandler, org.xml.sax.DTDHandler, org.xml.sax.ErrorHandler, org.xml.sax.ext.LexicalHandler

public class BufferingPipe
extends PipeHandler

SAX Pipe with ability to buffer SAX events into BufferingPipe(Object) object.

This is a genuine pipe element piping incoming SAX events to the assigned handler object. But it allow for a temporary diverting of the events into a BufferHandler object.

One can think of it as XML sub-tree splitter. When bufferInto(BufferHandler) is called it diverts the following XML sub-tree into the buffer and then resumes sending to the original handler (specified during construction time BufferingPipe(Object). It counts all start-end element events and keeps track of the element's depth in order to do that.

When bufferInto(BufferHandler) is called, it will remember current element's depth and pipe's hanlders and will replace them with given buffer. All consequent events will be forwarded to the buffer.

When events related to the inner XML elements are all received it will restore original pipe's hanlders automatically and continue forwarding events to them. created on Aug 17, 2006

Since:

Version:

$Revision: 1.3 $

Author:

fiykov

Field Summary

protected BufferHandler	buffer buffering object
protected int	elementDepth currently parsed element depth
protected boolean	inBufferMode flag which if true this pipe is in buffering mode
protected int	markedDepth elements depth when buffering occured

Constructor Summary

BufferingPipe()

BufferingPipe(java.lang.Object handler)
Construct a pipe forwarding all events to given handler

Method Summary

void	bufferInto(BufferHandler buffer) buffer all following events into given buffer.
void	endElement(java.lang.String uri, java.lang.String localName, java.lang.String qName) decreate nested elements counter and delegate to piped object
protected void	exitBufferingMode() exit buffering mode.
void	startElement(java.lang.String uri, java.lang.String localName, java.lang.String qName, org.xml.sax.Attributes atts) increate nested elements counter and delegate to piped object

Methods inherited from class net.sf.fikin.xml.sax.PipeHandler

characters, characters, comment, comment, endCDATA, endDocument, endDTD, endEntity, endPrefixMapping, error, fatalError, getContentHandler, getDocumentLocator, getDTDHandler, getErrorHandler, getLexicalHandler, ignorableWhitespace, ignorableWhitespace, notationDecl, processingInstruction, setContentHandler, setDocumentLocator, setDTDHandler, setErrorHandler, setHandler, setLexicalHandler, skippedEntity, startCDATA, startDocument, startDTD, startEntity, startPrefixMapping, unparsedEntityDecl, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

inBufferMode

protected boolean inBufferMode

flag which if true this pipe is in buffering mode

markedDepth

protected int markedDepth

elements depth when buffering occured

elementDepth

protected int elementDepth

currently parsed element depth

buffer

protected BufferHandler buffer

buffering object

Constructor Detail

BufferingPipe

public BufferingPipe()

BufferingPipe

public BufferingPipe(java.lang.Object handler)

Construct a pipe forwarding all events to given handler

Parameters:

handler - is an object implementing any or all of the following interfaces: DTDHandler, ContentHandler, ErrorHandler, LexicalHandler

Method Detail

bufferInto

public void bufferInto(BufferHandler buffer)

buffer all following events into given buffer. takes into account nested structure of the XML document by conting start-end element depth. when this method is called it will buffer all inner element events and then restore original pipe's hanlder automatically.

Parameters:

buffer -

exitBufferingMode

protected void exitBufferingMode()

exit buffering mode. restore orignal pipe hanlder

startElement

public void startElement(java.lang.String uri,
                         java.lang.String localName,
                         java.lang.String qName,
                         org.xml.sax.Attributes atts)
                  throws org.xml.sax.SAXException

increate nested elements counter and delegate to piped object

Specified by:

startElement in interface org.xml.sax.ContentHandler

Overrides:

startElement in class PipeHandler

Throws:

org.xml.sax.SAXException

endElement

public void endElement(java.lang.String uri,
                       java.lang.String localName,
                       java.lang.String qName)
                throws org.xml.sax.SAXException

decreate nested elements counter and delegate to piped object

Specified by:

endElement in interface org.xml.sax.ContentHandler

Overrides:

endElement in class PipeHandler

Throws:

org.xml.sax.SAXException