A plugin aggregate function. More...

Inheritance diagram for sb::PluginAggregate:

Public Member Functions
virtual	~PluginAggregate ()
	Virtual destructor. More...

virtual void	typecheck (const Schema &arg_types)
	Check to make sure the argument types are valid for this aggregate function. More...

virtual void	initialize ()=0
	Initialize any window state. More...

virtual void	increment (const Tuple &args)=0
	Add the values passed as parameters to the window state. More...

virtual void	calculate (Tuple &retval)=0
	Calculate the value of the aggregate over the values in the window. More...

virtual void	release ()
	Clear internal state. More...

virtual std::string	save ()
	Return a binary string containing the checkpoint state of this object. More...

virtual void	load (std::string data)
	Recover the state of this object from the argument, a binary string that was returned by a previous invocation of save() More...

Detailed Description

A plugin aggregate function.

Constructor & Destructor Documentation

virtual sb::PluginAggregate::~PluginAggregate ( )

inlinevirtual

Virtual destructor.

virtual void sb::PluginAggregate::calculate ( Tuple & retval )

pure virtual

Calculate the value of the aggregate over the values in the window.

initialize() will be called first. No guarantee that increment() will ever be called.

virtual void sb::PluginAggregate::increment ( const Tuple & args )

pure virtual

Add the values passed as parameters to the window state.

initialize() will be called first.

virtual void sb::PluginAggregate::initialize ( )

pure virtual

Initialize any window state.

Clear the window values, if any. Instances of PluginAggregate may be reused for multiple windows.

virtual void sb::PluginAggregate::load ( std::string data )

inlinevirtual

Recover the state of this object from the argument, a binary string that was returned by a previous invocation of save()

virtual void sb::PluginAggregate::release ( )

inlinevirtual

Clear internal state.

This method is called after this use of the aggregate is finished.

virtual std::string sb::PluginAggregate::save ( )

inlinevirtual

Return a binary string containing the checkpoint state of this object.

This string will be passed to the load() method if a checkpoint is loaded.

virtual void sb::PluginAggregate::typecheck ( const Schema & arg_types )

inlinevirtual

Check to make sure the argument types are valid for this aggregate function.

Parameters

arg_types The types of the arguments to this function.

Exceptions

TypecheckException if the argument types are not appropriate.

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