java - akka.persistence.typed.internal.JournalFailureException : Exception during recovery. 如何解决？

Question

使用 Akka 持久性我得到这个异常:

Caused by: akka.persistence.typed.internal.JournalFailureException: Exception during recovery. Last known sequence number [0]. PersistenceId [PersistenceExample], due to: Cannot construct instance of com.exercisePersistence.simpleExample.MyPersistentBehavior$Added (although at least one Creator exists): cannot deserialize from Object value (no delegate- or property-based Creator) at [Source: (byte[])"{"data":"data1"}"; line: 1, column: 2] at akka.persistence.typed.internal.ReplayingEvents.onRecoveryFailure(ReplayingEvents.scala:221) at akka.persistence.typed.internal.ReplayingEvents.onJournalResponse(ReplayingEvents.scala:143) ... 26 common frames omitted

Caused by: com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of com.exercisePersistence.simpleExample.MyPersistentBehavior$Added (although at least one Creator exists): cannot deserialize from Object value (no delegate- or property-based Creator) at [Source: (byte[])"{"data":"data1"}"; line: 1, column: 2]

添加的给我异常(exception)的类是:

public class MyPersistentBehavior 
    extends EventSourcedBehavior<MyPersistentBehavior.Command, 
        MyPersistentBehavior.Event, MyPersistentBehavior.State> {

    // COMMAND
    interface Command {}
    public static class Add implements Command {
      public final String data;

      public Add(String data) {
        this.data = data;
      }
    }
...
}

文件引用.conf

akka {
 actor {
serializers {
  jackson-json = "akka.serialization.jackson.JacksonJsonSerializer"
  jackson-cbor = "akka.serialization.jackson.JacksonCborSerializer"
  proto = "akka.remote.serialization.ProtobufSerializer"
}
serialization-bindings {
  "com.exercisePersistence.simpleExample.MyPersistentBehavior" = jackson-json
  "com.exercisePersistence.simpleExample.MyPersistentBehavior$Added" = jackson-json
  #"docs.serialization.CborSerializable" = jackson-cbor
  "com.google.protobuf.Message" = proto
}

}

akka.serialization.jackson {
      jackson-json-message {
        serialization-features {
          WRITE_DATES_AS_TIMESTAMPS = on
        }
      }
      jackson-json-event {
        serialization-features {
          WRITE_DATES_AS_TIMESTAMPS = off
        }
      }
  }
  persistence {
    journal {
      plugin = "leveldb"

      leveldb {
        dir = "target/persistence/journal"
      }
    }

    snapshot-store.local.dir = "target/persistence/snapshots"
  }
}

leveldb {
  dir = "target/persistence/journal"
  checksum: "off"
  class: "akka.persistence.journal.leveldb.LeveldbJournal"
  dir: "target/persistence/journal"
  fsync: "on"
  native: "on"
  plugin-dispatcher : "akka.persistence.dispatchers.default-plugin-dispatcher"
  replay-dispatcher : "akka.persistence.dispatchers.default-replay-dispatcher"
}

如果想克隆项目，这是 Github 链接:https://github.com/Mazzotta13/AkkaTutorial.git

Answer 1

您有几个不同的选择:

1. 由于您使用 Jackson 进行序列化，因此您可以向协议(protocol)对象中的构造函数添加 @JsonCreator 注释。
2. 您可以使用 Lombak 创建协议(protocol)对象，这样可以节省大量 Java 样板，并使用 @NoArgsConstructor 对其进行注释。
3. 创建一个空的构造函数。

有关它的一些信息可以在这里找到，https://doc.akka.io/docs/akka/current/serialization-jackson.html#annotations