A Short History of Complex Event Processing Part 3: the formative years
by David LuckhamIn “A Short History, Part 2″ we left off our story of CEP at a period of “hard times” for the vendors of CEP products during the years 2000 to 2007. This was the first of the four stages of Complex Event Processing.* It was the take-off stage for CEP.* Figure 1 in [...]
Event::generic(3pm) User Contributed Perl Documentation Event::generic(3pm)NAME
Event::generic - generic event handling
SYNOPSIS
use Event::generic;
$source = Event::generic::Source->new;
$w = Event->generic(source => $source, ...);
$w = $source->watch(...);
$source = $w->source;
$w->source($source);
$source->event;
$source->event($data);
$data = $event->data;
DESCRIPTION
This module provides a watcher type within the "Event" framework. You must understand the architecture of the "Event" system in order to
understand this document.
This module provides a system of reified event sources and watchers watching those sources. Events are generated solely by a method on the
event source object. The events may carry arbitrary data to the event handler callbacks. This module is intended for situations where the
events of interest are best determined by Perl code.
CLASSES
Event::generic::Source
A reified event source.
Event::generic
A watcher that can watch "Event::generic::Source" event sources.
Event::Event::Dataful
A (target) event that can carry arbitrary data.
EVENT SOURCE CLASS
Constructor
Event::generic::Source->new
Creates and returns a new event source.
Methods
$source->event
$source->event(DATA)
The invocation of this method is a source event for watchers of the event source. When this method is called, each active watcher of
the event source generates a target event. The DATA, if supplied, is copied into the target event objects, from which it can be
retrieved using the "data()" method.
$source->watch(ATTR => VALUE, ...)
Generates and returns a new watcher, configured to watch this event source. The standard watcher attributes may be specified as
arguments. The watcher returned is an ordinary "Event::generic", and may be reconfigured to watch a different event source.
WATCHER CLASS
Type-specific attributes
source => $source
The event source to watch. This must be either an "Event::generic::Source" object or "undef". When set to "undef", no source is being
watched, and the watcher cannot be started.
EVENT CLASS
Type-specific methods
$event->data
Returns the data associated with the event, which may be any scalar. This is read-only, and is set by the event source.
SEE ALSO
Event
perl v5.14.2 2007-05-22 Event::generic(3pm)