active-object-delphi
Active Object Concurrency Design Pattern Implemented in Delphi
- Quiet · last change 1-8-2023
- ★ 7 on GitHub
README
active-object-delphi
Active Object Concurrency Design Pattern Implemented in Delphi. A Proxy can wrap a Servant object and run requests to the Servant in a thread. The Servant object does not know of the concurrency system and the Proxy can present a similar interface as the Servant.
Source code for blog posts on the Active Object Pattern
Part 4: The Servant and the Proxy
procedure TProxy.put(const msg: TMessage);
var
LMsg: TMessage;
begin
LMsg := msg;
FScheduler.Equeue(
TMethodRequest.Create(
// Call
procedure
begin
FServant.put_i(LMsg);
end,
// Optional Guard
function : boolean
begin
result := not FServant.full_i;
end
)
);
end;I also provided a Future interface to enqueue methods that should return values.
function TProxy.get: IFutureValue<TMessage>;
var
LActiveFuture: TFutureValue<TMessage>;
begin
LActiveFuture := TFutureValue<TMessage>.Create;
result := LActiveFuture;
FScheduler.Enqueue(
TMethodRequest.Create(
// Call
procedure
begin
LActiveFuture.SetValue(FServant.get_i); // closure over the future and servant
end,
// Optional Guard
function : boolean
begin
result := not FServant.empty_i;
end
)
);
end;