public class ZActor extends ZStar
This implementation is based on the ZStar one (TODO via inheritance now but this is not totally stamped and the use of the ZAgent would probably limit the collateral damages if changed)
so you should be first familiar with the metaphor there.
To extensively sum up:
A side or endpoint designates the same thing: the thread where lives one of the two parts of the Actor system.
An actor has 2 sides (with a trial to use theater terms for fun (: and hopefully clarity :)
- the Corbeille side, or control side
This is where one can send and receive control messages to the underneath actor via the ZActor and/or its agent.
The ZActor lives on this side and is a way to safely communicate with the distant provided Actor
Note: Corbeille is a french word designing the most privileged seats in the theater,
1st floor, just above the orchestra (Wikipedia...).
It was the place where the King was standing during the shows, with the best seat of course!
Fast users who would want to communicate with the distant ZActor.Actor can use
ZStar.send(ZMsg) or ZStar.recv() from the ZActor as the ZActor is itself an agent!
- the Plateau side, or background side where all the performances are made by the provided actor.
The provided ZActor.Actor is living on the Plateau.
The Plateau is made of the Stage where the effective processing occurs and of the Backstage
where the provided actor can send and receive control messages to and from the ZActor.
From this side, the work is done via callbacks using the template-method pattern, applied with interfaces (?)
The main purpose (or at least its intent) of this class is to clarify the contracts, roles, responsibilities and action levers related to the Plateau.
The provided Actor will not be alone to do the processing of each loop.
It will be helped by a double responsible for passing the appropriate structures at the right moment.
As a developer point of view, this double helps also to limit the complexity of the process.
However Double is an uncommon one, capturing all the lights while letting the Actor taking care of all the invisible work in the shadows.
And this is one of the points where we begin to reach the limits of the metaphor...
The ZActor takes care of the establishment of the background processing, calling the provided Actor
at appropriate times via its Double. It can also manage the exited state on the control side,
if using the provided ZStar.send(ZMsg) or ZStar.recv() methods.
It also takes care of the automatic closing of sockets and context if it had to create one.
An actor is basically a contract interface that anyone who uses this ZActor SHALL comply to.
TODO This interface is still a little bit tough, as instead of the 5+2 Star callbacks, here are 10!
But they allow you to have a hand on the key points of the looping, restart a new actor if needed, ...
Anyway, adapters like a simple one or a duo are present to help you on that, reducing the amount of
methods to write.
PS: Je sais qu'il y a une différence entre acteur et comédien :) PPS: I know nothing about theater!
Example of code for a minimalistic actor with no socket handling other than the control pipe:
Actor acting = new ZActor.SimpleActor()
{
public List<Socket> createSockets(ZContext ctx, Object ... args)
{
assert ("TEST".equals(args[0]));
return Arrays.asList(ctx.createSocket(ZMQ.PUB));
}
public boolean backstage(Socket pipe, ZPoller poller, int events)
{
String cmd = pipe.recvStr();
if ("HELLO".equals(cmd)) {
pipe.send("WORLD");
// end of the actor
return false;
}
return true;
}
};
ZActor actor = new ZActor(acting, "LOCK", Arrays.asList("TEST").toArray());
Socket pipe = actor.pipe();
boolean rc = pipe.send("HELLO");
assert (rc);
ZMsg msg = actor.recv();
String world = msg.popString();
assert ("WORLD".equals(world));
msg = actor.recv();
assert (msg == null);
rc = actor.sign();
assert (!rc);
rc = actor.send("whatever");
assert (!rc);
// don't try to use the pipe
| Modifier and Type | Class and Description |
|---|---|
static interface |
ZActor.Actor
Defines the contract for the acting instance.
|
static class |
ZActor.Duo
Another actor will be called just before the main one,
without participating to the decisions.
|
static class |
ZActor.SimpleActor
Simple adapter for an actor, with no sockets, blocking calls and immediate termination.
|
ZStar.Entourage, ZStar.Exit, ZStar.Fortune, ZStar.Set, ZStar.SimpleSet, ZStar.Star, ZStar.TimeTakerZAgent.Creator, ZAgent.SelectorCreator, ZAgent.SimpleAgent, ZAgent.VerySimpleSelectorCreator| Constructor and Description |
|---|
ZActor(ZActor.Actor actor,
String motdelafin,
Object... args)
Creates a new ZActor.
|
ZActor(ZAgent.SelectorCreator selector,
ZActor.Actor actor,
String motdelafin,
Object... args)
Creates a new ZActor.
|
ZActor(ZContext context,
ZActor.Actor actor,
String motdelafin,
Object... args)
Creates a new ZActor.
|
ZActor(ZContext context,
ZAgent.SelectorCreator selector,
ZActor.Actor actor,
String motdelafin,
Object... args)
Creates a new ZActor.
|
public ZActor(ZActor.Actor actor, String motdelafin, Object... args)
actor - the actor handling messages from either stage and backstageargs - the optional arguments that will be passed to the distant actorpublic ZActor(ZAgent.SelectorCreator selector, ZActor.Actor actor, String motdelafin, Object... args)
selector - the creator of the selector used on the Plateau.actor - the actor handling messages from either stage and backstageargs - the optional arguments that will be passed to the distant actorpublic ZActor(ZContext context, ZAgent.SelectorCreator selector, ZActor.Actor actor, String motdelafin, Object... args)
context - the main context used. If null, a new context will be created
and closed at the stop of the operation.
If not null, it is the responsibility of the caller to close it.selector - the creator of the selector used on the Plateau.actor - the actor handling messages from either stage and backstageargs - the optional arguments that will be passed to the distant actorpublic ZActor(ZContext context, ZActor.Actor actor, String motdelafin, Object... args)
context - the main context used. If null, a new context will be created
and closed at the stop of the operation.
If not null, it is the responsibility of the caller to close it.actor - the actor handling messages from either stage and backstageargs - the optional arguments that will be passed to the distant actorCopyright © 2017. All rights reserved.