!per #3707 Channel enhancements

- Persistent channel
- ConfirmablePersistent message type delivered by channel
- Sender resolution performance improvements
   * unstash() instead of unstashAll()

These enhancements required the following changes

- Unified implementation of processor stash and user stash
- Persistence message plugin API separated from implementation
- Physical deletion of messages

akka-docs/rst/java/code/docs/persistence/PersistenceDocTest.java

@@ -142,8 +142,8 @@ public class PersistenceDocTest {
 
         class MyDestination extends UntypedActor {
             public void onReceive(Object message) throws Exception {
-                if (message instanceof Persistent) {
-                    Persistent p = (Persistent)message;
+                if (message instanceof ConfirmablePersistent) {
+                    ConfirmablePersistent p = (ConfirmablePersistent)message;
                     System.out.println("received " + p.payload());
                     p.confirm();
                 }
@@ -266,4 +266,19 @@ public class PersistenceDocTest {
         }
         //#batch-write
     };
+
+    static Object o7 = new Object() {
+        abstract class MyProcessor extends UntypedProcessor {
+            ActorRef destination;
+
+            public void foo() {
+                //#persistent-channel-example
+                final ActorRef channel = getContext().actorOf(PersistentChannel.props(),
+                        "myPersistentChannel");
+
+                channel.tell(Deliver.create(Persistent.create("example"), destination), getSelf());
+                //#persistent-channel-example
+            }
+        }
+    };
 }

akka-docs/rst/java/code/docs/persistence/PersistencePluginDocTest.java

@@ -36,22 +36,22 @@ public class PersistencePluginDocTest {
 
     class MyAsyncJournal extends AsyncWriteJournal {
         @Override
-        public Future<Long> doReplayAsync(String processorId, long fromSequenceNr, long toSequenceNr, Procedure<PersistentImpl> replayCallback) {
+        public Future<Long> doReplayAsync(String processorId, long fromSequenceNr, long toSequenceNr, Procedure<PersistentRepr> replayCallback) {
             return null;
         }
 
         @Override
-        public Future<Void> doWriteAsync(PersistentImpl persistent) {
+        public Future<Void> doWriteAsync(PersistentRepr persistent) {
             return null;
         }
 
         @Override
-        public Future<Void> doWriteBatchAsync(Iterable<PersistentImpl> persistentBatch) {
+        public Future<Void> doWriteBatchAsync(Iterable<PersistentRepr> persistentBatch) {
             return null;
         }
 
         @Override
-        public Future<Void> doDeleteAsync(PersistentImpl persistent) {
+        public Future<Void> doDeleteAsync(String processorId, long sequenceNr, boolean physical) {
             return null;
         }