ConverterBox Class Reference

#include <ConverterBox.h>

Inherited by SimpleConverterBox.

List of all members.

---

Detailed Description

Converts data received on a network port to tuples on a single stream.

There are three ways to write a converter box to handle custom-formatted data from the network. In order of decreasing generality but increasing ease of use:

• To receive and process arbitrary bytes directly from the network, create a subclass of ConverterBox and implement the ConverterBox::handleData() method. handleData() is called whenever new data arrive on the network.

• To process delimited or fixed-size records, create a subclass of SimpleConverterBox and implement the SimpleConverterBox::convertTuple() method. convertTuple() is called whenever a single, complete input record is received.

• To process records which match POSIX extended regular expressions, create a subclass of RegexConverterBox and implement the RegexConverterBox::convertTupleFromRegex() method. convertTupleFromRegex() is called whenever a single, complete input record matching the regex is received; the method is supplied the subexpressions matched by the regex.

Include the AURORA_DECLARE_CONVERTER_BOX(ClassName) macro inside the class declaration for your converter box, and AURORA_DEFINE_CONVERTER_BOX(ClassName) in the definition of your box (ClassName.C).

Once you have written a converter box, you may add a line like the following to your Aurora configuration file, to bind your converter box to a particular network port and tuple stream:

    <converter-box class='StockQuoteConverterBox'
                   port='30000'
                   stream='stock-quotes'/>
    

This listens for stock quotes on port 30000, and uses StockQuoteConverterBox to convert input records to tuples on the stock-quotes stream.

Public Member Functions
virtual	~ConverterBox ()
	Destructor.
TupleDescription	getSchema () const
	Returns the schema describing tuples generated by this converter box.
virtual unsigned int	handleData (constbuf input)=0 throw (AuroraException)
	Handles incoming data to be converted.
void	setStream (ptr< Stream > stream)
	Sets the stream that will receive data generated by this converter box.
ptr< Stream >	getStream ()
	Returns the stream that will receive data generated by this converter box.
Protected Member Functions
	ConverterBox (TupleDescription schema)
	Create a converter box that generates tuples with a given schema.

---

Constructor & Destructor Documentation

ConverterBox::ConverterBox (  TupleDescription  schema  )  [protected]

Create a converter box that generates tuples with a given schema.

ConverterBox::~ConverterBox (   )  [virtual]

Destructor.

---

Member Function Documentation

TupleDescription ConverterBox::getSchema (   )  const

Returns the schema describing tuples generated by this converter box. (This is the schema provided to the constructor.)

ptr<Stream> ConverterBox::getStream (   )

Returns the stream that will receive data generated by this converter box.

virtual unsigned int ConverterBox::handleData (  constbuf  input  )  throw (AuroraException) [pure virtual]

Handles incoming data to be converted. Must be implemented by the subclass; the subclass should examine the incoming bytes, and enqueue data as necessary on the stream returned by the getStream() method. Parameters: input  data to be handled by the converter box. Returns: the number of bytes consumed by the converter box. Any remaining bytes will be buffered and presented to the box again when more bytes arrive. Implemented in SimpleConverterBox.

void ConverterBox::setStream (  ptr< Stream >  stream  )

Sets the stream that will receive data generated by this converter box.

---

The documentation for this class was generated from the following files:

• ConverterBox.h
• ConverterBox.cc

---