=per #3774 Persistence activator templates

2014-02-03 16:08:19 +01:00 · 2014-02-03 16:08:19 +01:00 · cf6e61e45a
commit cf6e61e45a
parent 1e86e6436b
31 changed files with 518 additions and 76 deletions
--- a/akka-samples/akka-sample-persistence-java/src/main/java/sample/persistence/EventsourcedExample.java
+++ b/akka-samples/akka-sample-persistence-java/src/main/java/sample/persistence/EventsourcedExample.java
@ -0,0 +1,141 @@
+/**
+ * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
+ */
+
+package sample.persistence;
+
+//#eventsourced-example
+import java.io.Serializable;
+import java.util.ArrayList;
+
+import akka.actor.*;
+import akka.japi.Procedure;
+import akka.persistence.*;
+
+import static java.util.Arrays.asList;
+
+class Cmd implements Serializable {
+    private final String data;
+
+    public Cmd(String data) {
+        this.data = data;
+    }
+
+    public String getData() {
+        return data;
+    }
+}
+
+class Evt implements Serializable {
+    private final String data;
+
+    public Evt(String data) {
+        this.data = data;
+    }
+
+    public String getData() {
+        return data;
+    }
+}
+
+class ExampleState implements Serializable {
+    private final ArrayList<String> events;
+
+    public ExampleState() {
+        this(new ArrayList<String>());
+    }
+
+    public ExampleState(ArrayList<String> events) {
+        this.events = events;
+    }
+
+    public ExampleState copy() {
+        return new ExampleState(new ArrayList<String>(events));
+    }
+
+    public void update(Evt evt) {
+        events.add(evt.getData());
+    }
+
+    public int size() {
+        return events.size();
+    }
+
+    @Override
+    public String toString() {
+        return events.toString();
+    }
+}
+
+class ExampleProcessor extends UntypedEventsourcedProcessor {
+    private ExampleState state = new ExampleState();
+
+    public int getNumEvents() {
+        return state.size();
+    }
+
+    public void onReceiveRecover(Object msg) {
+        if (msg instanceof Evt) {
+            state.update((Evt) msg);
+        } else if (msg instanceof SnapshotOffer) {
+            state = (ExampleState)((SnapshotOffer)msg).snapshot();
+        }
+    }
+
+    public void onReceiveCommand(Object msg) {
+        if (msg instanceof Cmd) {
+            final String data = ((Cmd)msg).getData();
+            final Evt evt1 = new Evt(data + "-" + getNumEvents());
+            final Evt evt2 = new Evt(data + "-" + (getNumEvents() + 1));
+            persist(asList(evt1, evt2), new Procedure<Evt>() {
+                public void apply(Evt evt) throws Exception {
+                    state.update(evt);
+                    if (evt.equals(evt2)) {
+                        getContext().system().eventStream().publish(evt);
+                        if (data.equals("foo")) getContext().become(otherCommandHandler);
+                    }
+                }
+            });
+        } else if (msg.equals("snap")) {
+            // IMPORTANT: create a copy of snapshot
+            // because ExampleState is mutable !!!
+            saveSnapshot(state.copy());
+        } else if (msg.equals("print")) {
+            System.out.println(state);
+        }
+    }
+
+    private Procedure<Object> otherCommandHandler = new Procedure<Object>() {
+        public void apply(Object msg) throws Exception {
+            if (msg instanceof Cmd && ((Cmd)msg).getData().equals("bar")) {
+                persist(new Evt("bar-" + getNumEvents()), new Procedure<Evt>() {
+                    public void apply(Evt event) throws Exception {
+                        state.update(event);
+                        getContext().unbecome();
+                    }
+                });
+                unstashAll();
+            } else {
+                stash();
+            }
+        }
+    };
+}
+//#eventsourced-example
+
+public class EventsourcedExample {
+    public static void main(String... args) throws Exception {
+        final ActorSystem system = ActorSystem.create("example");
+        final ActorRef processor = system.actorOf(Props.create(ExampleProcessor.class), "processor-4-java");
+
+        processor.tell(new Cmd("foo"), null);
+        processor.tell(new Cmd("baz"), null);
+        processor.tell(new Cmd("bar"), null);
+        processor.tell("snap", null);
+        processor.tell(new Cmd("buzz"), null);
+        processor.tell("print", null);
+
+        Thread.sleep(1000);
+        system.shutdown();
+    }
+}