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240 | with
lace.Event.Logger,
lace.Event.utility,
system.RPC,
ada.unchecked_Deallocation;
package body lace.make_Subject
is
use type Event.Logger.view;
procedure destroy (Self : in out Item)
is
begin
Self.safe_Observers.destruct;
end destroy;
-------------
-- Attributes
--
overriding
function Observers (Self : in Item; of_Kind : in Event.Kind) return subject.Observer_views
is
begin
return Self.safe_Observers.fetch_Observers (of_Kind);
end Observers;
overriding
function observer_Count (Self : in Item) return Natural
is
begin
return Self.safe_Observers.observer_Count;
end observer_Count;
-------------
-- Operations
--
overriding
procedure register (Self : access Item; the_Observer : in Observer.view;
of_Kind : in Event.Kind)
is
begin
Self.safe_Observers.add (the_Observer, of_Kind);
if Subject.Logger /= null
then
Subject.Logger.log_Connection (the_Observer,
Subject.view (Self),
of_Kind);
end if;
end register;
overriding
procedure deregister (Self : in out Item; the_Observer : in Observer.view;
of_Kind : in Event.Kind)
is
begin
Self.safe_Observers.rid (the_Observer, of_Kind);
if Subject.Logger /= null
then
Subject.Logger.log_disconnection (the_Observer,
Self'unchecked_Access,
of_Kind);
end if;
end deregister;
overriding
procedure emit (Self : access Item; the_Event : in Event.item'Class := Event.null_Event)
is
use lace.Event.utility;
my_Observers : constant Subject.Observer_views := Self.Observers (to_Kind (the_Event'Tag));
begin
for i in my_Observers'Range
loop
begin
my_Observers (i).receive (the_Event,
from_Subject => Subject.item'Class (Self.all).Name);
if Subject.Logger /= null
then
Subject.Logger.log_Emit (Subject.view (Self),
my_Observers (i),
the_Event);
end if;
exception
when system.RPC.communication_Error
| storage_Error =>
if Subject.Logger /= null
then
Subject.Logger.log_Emit (Subject.view (Self),
my_Observers (i),
the_Event);
end if;
end;
end loop;
end emit;
overriding
function emit (Self : access Item; the_Event : in Event.item'Class := Event.null_Event)
return subject.Observer_views
is
use lace.Event.utility;
my_Observers : constant Subject.Observer_views := Self.Observers (to_Kind (the_Event'Tag));
bad_Observers : Subject.Observer_views (my_Observers'Range);
bad_Count : Natural := 0;
begin
for i in my_Observers'Range
loop
begin
my_Observers (i).receive (the_Event,
from_Subject => Subject.item'Class (Self.all).Name);
if Subject.Logger /= null
then
Subject.Logger.log_Emit (Subject.view (Self),
my_Observers (i),
the_Event);
end if;
exception
when system.RPC.communication_Error
| storage_Error =>
bad_Count := bad_Count + 1;
bad_Observers (bad_Count) := my_Observers (i);
end;
end loop;
return bad_Observers (1 .. bad_Count);
end emit;
-----------------
-- Safe Observers
--
protected
body safe_Observers
is
procedure destruct
is
use event_kind_Maps_of_event_observers;
procedure deallocate is new ada.unchecked_Deallocation (event_Observer_Vector,
event_Observer_Vector_view);
Cursor : event_kind_Maps_of_event_observers.Cursor := the_Observers.First;
the_event_Observer_Vector : event_Observer_Vector_view;
begin
while has_Element (Cursor)
loop
the_event_Observer_Vector := Element (Cursor);
deallocate (the_event_Observer_Vector);
next (Cursor);
end loop;
end destruct;
procedure add (the_Observer : in Observer.view;
of_Kind : in Event.Kind)
is
use event_Observer_Vectors,
event_kind_Maps_of_event_observers;
Cursor : constant event_kind_Maps_of_event_observers.Cursor := the_Observers.find (of_Kind);
the_event_Observers : event_Observer_Vector_view;
begin
if has_Element (Cursor)
then
the_event_Observers := Element (Cursor);
else
the_event_Observers := new event_Observer_Vector;
the_Observers.insert (of_Kind,
the_event_Observers);
end if;
the_event_Observers.append (the_Observer);
end add;
procedure rid (the_Observer : in Observer.view;
of_Kind : in Event.Kind)
is
the_event_Observers : event_Observer_Vector renames the_Observers.Element (of_Kind).all;
begin
the_event_Observers.delete (the_event_Observers.find_Index (the_Observer));
end rid;
function fetch_Observers (of_Kind : in Event.Kind) return subject.Observer_views
is
begin
if the_Observers.Contains (of_Kind)
then
declare
the_event_Observers : constant event_Observer_Vector_view := the_Observers.Element (of_Kind);
my_Observers : Subject.Observer_views (1 .. Natural (the_event_Observers.Length));
begin
for i in my_Observers'Range
loop
my_Observers (i) := the_event_Observers.Element (i);
end loop;
return my_Observers;
end;
else
return (1 .. 0 => <>);
end if;
end fetch_Observers;
function observer_Count return Natural
is
use event_kind_Maps_of_event_observers;
Cursor : event_kind_Maps_of_event_observers.Cursor := the_Observers.First;
Count : Natural := 0;
begin
while has_Element (Cursor)
loop
Count := Count + Natural (Element (Cursor).Length);
next (Cursor);
end loop;
return Count;
end observer_Count;
end safe_Observers;
end lace.make_Subject;
|