606 lines
20 KiB
Java
606 lines
20 KiB
Java
/**
|
|
* Copyright (C) 2009-2016 Lightbend Inc. <http://www.lightbend.com>
|
|
*/
|
|
|
|
package docs.persistence;
|
|
|
|
import java.util.concurrent.TimeUnit;
|
|
|
|
import akka.actor.*;
|
|
import akka.pattern.BackoffSupervisor;
|
|
import scala.concurrent.duration.Duration;
|
|
import akka.japi.Function;
|
|
import akka.japi.Procedure;
|
|
import akka.persistence.*;
|
|
|
|
import java.io.Serializable;
|
|
|
|
public class PersistenceDocTest {
|
|
|
|
public interface SomeOtherMessage {}
|
|
|
|
public interface PersistentActorMethods {
|
|
//#persistence-id
|
|
public String persistenceId();
|
|
//#persistence-id
|
|
//#recovery-status
|
|
public boolean recoveryRunning();
|
|
public boolean recoveryFinished();
|
|
//#recovery-status
|
|
}
|
|
|
|
static Object o2 = new Object() {
|
|
abstract class MyPersistentActor1 extends UntypedPersistentActor {
|
|
//#recovery-disabled
|
|
@Override
|
|
public Recovery recovery() {
|
|
return Recovery.none();
|
|
}
|
|
//#recovery-disabled
|
|
}
|
|
|
|
abstract class MyPersistentActor2 extends UntypedPersistentActor {
|
|
//#recovery-custom
|
|
@Override
|
|
public Recovery recovery() {
|
|
return Recovery.create(457L);
|
|
}
|
|
//#recovery-custom
|
|
}
|
|
|
|
class MyPersistentActor4 extends UntypedPersistentActor implements PersistentActorMethods {
|
|
//#persistence-id-override
|
|
@Override
|
|
public String persistenceId() {
|
|
return "my-stable-persistence-id";
|
|
}
|
|
//#persistence-id-override
|
|
@Override
|
|
public void onReceiveRecover(Object message) throws Exception {}
|
|
@Override
|
|
public void onReceiveCommand(Object message) throws Exception {}
|
|
}
|
|
|
|
class MyPersistentActor5 extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() {
|
|
return "persistence-id";
|
|
}
|
|
|
|
//#recovery-completed
|
|
@Override
|
|
public void onReceiveRecover(Object message) {
|
|
if (message instanceof RecoveryCompleted) {
|
|
// perform init after recovery, before any other messages
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object message) throws Exception {
|
|
if (message instanceof String) {
|
|
// ...
|
|
} else {
|
|
unhandled(message);
|
|
}
|
|
}
|
|
//#recovery-completed
|
|
}
|
|
|
|
abstract class MyActor extends UntypedPersistentActor {
|
|
//#backoff
|
|
@Override
|
|
public void preStart() throws Exception {
|
|
final Props childProps = Props.create(MyPersistentActor1.class);
|
|
final Props props = BackoffSupervisor.props(
|
|
childProps,
|
|
"myActor",
|
|
Duration.create(3, TimeUnit.SECONDS),
|
|
Duration.create(30, TimeUnit.SECONDS),
|
|
0.2);
|
|
getContext().actorOf(props, "mySupervisor");
|
|
super.preStart();
|
|
}
|
|
//#backoff
|
|
}
|
|
};
|
|
|
|
static Object atLeastOnceExample = new Object() {
|
|
//#at-least-once-example
|
|
|
|
class Msg implements Serializable {
|
|
public final long deliveryId;
|
|
public final String s;
|
|
|
|
public Msg(long deliveryId, String s) {
|
|
this.deliveryId = deliveryId;
|
|
this.s = s;
|
|
}
|
|
}
|
|
|
|
class Confirm implements Serializable {
|
|
public final long deliveryId;
|
|
|
|
public Confirm(long deliveryId) {
|
|
this.deliveryId = deliveryId;
|
|
}
|
|
}
|
|
|
|
|
|
class MsgSent implements Serializable {
|
|
public final String s;
|
|
|
|
public MsgSent(String s) {
|
|
this.s = s;
|
|
}
|
|
}
|
|
class MsgConfirmed implements Serializable {
|
|
public final long deliveryId;
|
|
|
|
public MsgConfirmed(long deliveryId) {
|
|
this.deliveryId = deliveryId;
|
|
}
|
|
}
|
|
|
|
class MyPersistentActor extends UntypedPersistentActorWithAtLeastOnceDelivery {
|
|
private final ActorSelection destination;
|
|
|
|
@Override
|
|
public String persistenceId() { return "persistence-id"; }
|
|
|
|
public MyPersistentActor(ActorSelection destination) {
|
|
this.destination = destination;
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object message) {
|
|
if (message instanceof String) {
|
|
String s = (String) message;
|
|
persist(new MsgSent(s), new Procedure<MsgSent>() {
|
|
public void apply(MsgSent evt) {
|
|
updateState(evt);
|
|
}
|
|
});
|
|
} else if (message instanceof Confirm) {
|
|
Confirm confirm = (Confirm) message;
|
|
persist(new MsgConfirmed(confirm.deliveryId), new Procedure<MsgConfirmed>() {
|
|
public void apply(MsgConfirmed evt) {
|
|
updateState(evt);
|
|
}
|
|
});
|
|
} else {
|
|
unhandled(message);
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object event) {
|
|
updateState(event);
|
|
}
|
|
|
|
void updateState(Object event) {
|
|
if (event instanceof MsgSent) {
|
|
final MsgSent evt = (MsgSent) event;
|
|
deliver(destination, new Function<Long, Object>() {
|
|
public Object apply(Long deliveryId) {
|
|
return new Msg(deliveryId, evt.s);
|
|
}
|
|
});
|
|
} else if (event instanceof MsgConfirmed) {
|
|
final MsgConfirmed evt = (MsgConfirmed) event;
|
|
confirmDelivery(evt.deliveryId);
|
|
}
|
|
}
|
|
}
|
|
|
|
class MyDestination extends UntypedActor {
|
|
public void onReceive(Object message) throws Exception {
|
|
if (message instanceof Msg) {
|
|
Msg msg = (Msg) message;
|
|
// ...
|
|
getSender().tell(new Confirm(msg.deliveryId), getSelf());
|
|
} else {
|
|
unhandled(message);
|
|
}
|
|
}
|
|
}
|
|
//#at-least-once-example
|
|
};
|
|
|
|
static Object o4 = new Object() {
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() { return "persistence-id"; }
|
|
|
|
//#save-snapshot
|
|
private Object state;
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object message) {
|
|
if (message.equals("snap")) {
|
|
saveSnapshot(state);
|
|
} else if (message instanceof SaveSnapshotSuccess) {
|
|
SnapshotMetadata metadata = ((SaveSnapshotSuccess)message).metadata();
|
|
// ...
|
|
} else if (message instanceof SaveSnapshotFailure) {
|
|
SnapshotMetadata metadata = ((SaveSnapshotFailure)message).metadata();
|
|
// ...
|
|
}
|
|
}
|
|
//#save-snapshot
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object event) {
|
|
}
|
|
}
|
|
|
|
};
|
|
|
|
static Object o5 = new Object() {
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
|
|
//#snapshot-criteria
|
|
@Override
|
|
public Recovery recovery() {
|
|
return Recovery.create(
|
|
SnapshotSelectionCriteria
|
|
.create(457L, System.currentTimeMillis()));
|
|
}
|
|
//#snapshot-criteria
|
|
|
|
@Override
|
|
public String persistenceId() { return "persistence-id"; }
|
|
|
|
//#snapshot-offer
|
|
private Object state;
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object message) {
|
|
if (message instanceof SnapshotOffer) {
|
|
state = ((SnapshotOffer)message).snapshot();
|
|
// ...
|
|
} else if (message instanceof RecoveryCompleted) {
|
|
// ...
|
|
} else {
|
|
// ...
|
|
}
|
|
}
|
|
//#snapshot-offer
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object message) {
|
|
}
|
|
}
|
|
|
|
};
|
|
|
|
static Object o9 = new Object() {
|
|
//#persist-async
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() { return "some-persistence-id"; }
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object msg) {
|
|
// handle recovery here
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object msg) {
|
|
sender().tell(msg, self());
|
|
|
|
persistAsync(String.format("evt-%s-1", msg), new Procedure<String>(){
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
}
|
|
});
|
|
persistAsync(String.format("evt-%s-2", msg), new Procedure<String>(){
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
}
|
|
});
|
|
}
|
|
}
|
|
//#persist-async
|
|
|
|
public void usage() {
|
|
final ActorSystem system = ActorSystem.create("example");
|
|
//#persist-async-usage
|
|
final ActorRef persistentActor = system.actorOf(Props.create(MyPersistentActor.class));
|
|
persistentActor.tell("a", null);
|
|
persistentActor.tell("b", null);
|
|
|
|
// possible order of received messages:
|
|
// a
|
|
// b
|
|
// evt-a-1
|
|
// evt-a-2
|
|
// evt-b-1
|
|
// evt-b-2
|
|
//#persist-async-usage
|
|
}
|
|
};
|
|
|
|
static Object o10 = new Object() {
|
|
//#defer
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() { return "some-persistence-id"; }
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object msg) {
|
|
// handle recovery here
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object msg) {
|
|
final Procedure<String> replyToSender = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
}
|
|
};
|
|
|
|
persistAsync(String.format("evt-%s-1", msg), replyToSender);
|
|
persistAsync(String.format("evt-%s-2", msg), replyToSender);
|
|
deferAsync(String.format("evt-%s-3", msg), replyToSender);
|
|
}
|
|
}
|
|
//#defer
|
|
|
|
public void usage() {
|
|
final ActorSystem system = ActorSystem.create("example");
|
|
//#defer-caller
|
|
final ActorRef persistentActor = system.actorOf(Props.create(MyPersistentActor.class));
|
|
persistentActor.tell("a", null);
|
|
persistentActor.tell("b", null);
|
|
|
|
// order of received messages:
|
|
// a
|
|
// b
|
|
// evt-a-1
|
|
// evt-a-2
|
|
// evt-a-3
|
|
// evt-b-1
|
|
// evt-b-2
|
|
// evt-b-3
|
|
//#defer-caller
|
|
}
|
|
};
|
|
|
|
static Object o11 = new Object() {
|
|
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() {
|
|
return "my-stable-persistence-id";
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object msg) {
|
|
// handle recovery here
|
|
}
|
|
|
|
//#nested-persist-persist
|
|
@Override
|
|
public void onReceiveCommand(Object msg) {
|
|
final Procedure<String> replyToSender = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
}
|
|
};
|
|
|
|
final Procedure<String> outer1Callback = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
persist(String.format("%s-inner-1", msg), replyToSender);
|
|
}
|
|
};
|
|
final Procedure<String> outer2Callback = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
persist(String.format("%s-inner-2", msg), replyToSender);
|
|
}
|
|
};
|
|
|
|
persist(String.format("%s-outer-1", msg), outer1Callback);
|
|
persist(String.format("%s-outer-2", msg), outer2Callback);
|
|
}
|
|
//#nested-persist-persist
|
|
|
|
void usage(ActorRef persistentActor) {
|
|
//#nested-persist-persist-caller
|
|
persistentActor.tell("a", self());
|
|
persistentActor.tell("b", self());
|
|
|
|
// order of received messages:
|
|
// a
|
|
// a-outer-1
|
|
// a-outer-2
|
|
// a-inner-1
|
|
// a-inner-2
|
|
// and only then process "b"
|
|
// b
|
|
// b-outer-1
|
|
// b-outer-2
|
|
// b-inner-1
|
|
// b-inner-2
|
|
|
|
//#nested-persist-persist-caller
|
|
}
|
|
}
|
|
|
|
|
|
class MyPersistAsyncActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() {
|
|
return "my-stable-persistence-id";
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object msg) {
|
|
// handle recovery here
|
|
}
|
|
|
|
//#nested-persistAsync-persistAsync
|
|
@Override
|
|
public void onReceiveCommand(Object msg) {
|
|
final Procedure<String> replyToSender = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
}
|
|
};
|
|
|
|
final Procedure<String> outer1Callback = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
persistAsync(String.format("%s-inner-1", msg), replyToSender);
|
|
}
|
|
};
|
|
final Procedure<String> outer2Callback = new Procedure<String>() {
|
|
@Override
|
|
public void apply(String event) throws Exception {
|
|
sender().tell(event, self());
|
|
persistAsync(String.format("%s-inner-1", msg), replyToSender);
|
|
}
|
|
};
|
|
|
|
persistAsync(String.format("%s-outer-1", msg), outer1Callback);
|
|
persistAsync(String.format("%s-outer-2", msg), outer2Callback);
|
|
}
|
|
//#nested-persistAsync-persistAsync
|
|
|
|
|
|
void usage(ActorRef persistentActor) {
|
|
//#nested-persistAsync-persistAsync-caller
|
|
persistentActor.tell("a", ActorRef.noSender());
|
|
persistentActor.tell("b", ActorRef.noSender());
|
|
|
|
// order of received messages:
|
|
// a
|
|
// b
|
|
// a-outer-1
|
|
// a-outer-2
|
|
// b-outer-1
|
|
// b-outer-2
|
|
// a-inner-1
|
|
// a-inner-2
|
|
// b-inner-1
|
|
// b-inner-2
|
|
|
|
// which can be seen as the following causal relationship:
|
|
// a -> a-outer-1 -> a-outer-2 -> a-inner-1 -> a-inner-2
|
|
// b -> b-outer-1 -> b-outer-2 -> b-inner-1 -> b-inner-2
|
|
|
|
//#nested-persistAsync-persistAsync-caller
|
|
}
|
|
}
|
|
};
|
|
|
|
static Object o14 = new Object() {
|
|
//#view
|
|
class MyView extends UntypedPersistentView {
|
|
@Override
|
|
public String persistenceId() { return "some-persistence-id"; }
|
|
|
|
@Override
|
|
public String viewId() { return "my-stable-persistence-view-id"; }
|
|
|
|
@Override
|
|
public void onReceive(Object message) throws Exception {
|
|
if (isPersistent()) {
|
|
// handle message from Journal...
|
|
} else if (message instanceof String) {
|
|
// handle message from user...
|
|
} else {
|
|
unhandled(message);
|
|
}
|
|
}
|
|
}
|
|
//#view
|
|
|
|
public void usage() {
|
|
final ActorSystem system = ActorSystem.create("example");
|
|
//#view-update
|
|
final ActorRef view = system.actorOf(Props.create(MyView.class));
|
|
view.tell(Update.create(true), null);
|
|
//#view-update
|
|
}
|
|
};
|
|
|
|
static Object o13 = new Object() {
|
|
//#safe-shutdown
|
|
final class Shutdown {}
|
|
|
|
class MyPersistentActor extends UntypedPersistentActor {
|
|
@Override
|
|
public String persistenceId() {
|
|
return "some-persistence-id";
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveCommand(Object msg) throws Exception {
|
|
if (msg instanceof Shutdown) {
|
|
context().stop(self());
|
|
} else if (msg instanceof String) {
|
|
System.out.println(msg);
|
|
persist("handle-" + msg, new Procedure<String>() {
|
|
@Override
|
|
public void apply(String param) throws Exception {
|
|
System.out.println(param);
|
|
}
|
|
});
|
|
} else unhandled(msg);
|
|
}
|
|
|
|
@Override
|
|
public void onReceiveRecover(Object msg) throws Exception {
|
|
// handle recovery...
|
|
}
|
|
}
|
|
//#safe-shutdown
|
|
|
|
|
|
public void usage() {
|
|
final ActorSystem system = ActorSystem.create("example");
|
|
final ActorRef persistentActor = system.actorOf(Props.create(MyPersistentActor.class));
|
|
//#safe-shutdown-example-bad
|
|
// UN-SAFE, due to PersistentActor's command stashing:
|
|
persistentActor.tell("a", ActorRef.noSender());
|
|
persistentActor.tell("b", ActorRef.noSender());
|
|
persistentActor.tell(PoisonPill.getInstance(), ActorRef.noSender());
|
|
// order of received messages:
|
|
// a
|
|
// # b arrives at mailbox, stashing; internal-stash = [b]
|
|
// # PoisonPill arrives at mailbox, stashing; internal-stash = [b, Shutdown]
|
|
// PoisonPill is an AutoReceivedMessage, is handled automatically
|
|
// !! stop !!
|
|
// Actor is stopped without handling `b` nor the `a` handler!
|
|
//#safe-shutdown-example-bad
|
|
|
|
//#safe-shutdown-example-good
|
|
// SAFE:
|
|
persistentActor.tell("a", ActorRef.noSender());
|
|
persistentActor.tell("b", ActorRef.noSender());
|
|
persistentActor.tell(new Shutdown(), ActorRef.noSender());
|
|
// order of received messages:
|
|
// a
|
|
// # b arrives at mailbox, stashing; internal-stash = [b]
|
|
// # Shutdown arrives at mailbox, stashing; internal-stash = [b, Shutdown]
|
|
// handle-a
|
|
// # unstashing; internal-stash = [Shutdown]
|
|
// b
|
|
// handle-b
|
|
// # unstashing; internal-stash = []
|
|
// Shutdown
|
|
// -- stop --
|
|
//#safe-shutdown-example-good
|
|
}
|
|
};
|
|
}
|