使用scala在kafka中创建自定义序列化程序和反序列化程序

我使用的是kafka_2.10-0.10.0.1和scala_2.10.3。 我想使用scala编写自定义序列化程序和反序列化程序。 我尝试使用以下序列化程序（来自CustomType）和反序列化程序（获取CustomType）：

但是，我有一个错误：

Exception in thread "main" org.apache.kafka.common.errors.SerializationException: Error deserializing key/value for partition topic_0_1-1 at offset 26
Caused by: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2 path $
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:224)
at com.google.gson.Gson.fromJson(Gson.java:887)
at com.google.gson.Gson.fromJson(Gson.java:852)
at com.google.gson.Gson.fromJson(Gson.java:801)
at kafka.PSDeserializer.deserialize(PSDeserializer.scala:24)
at kafka.PSDeserializer.deserialize(PSDeserializer.scala:18)
at org.apache.kafka.clients.consumer.internals.Fetcher.parseRecord(Fetcher.java:627)
at org.apache.kafka.clients.consumer.internals.Fetcher.parseFetchedData(Fetcher.java:548)
at org.apache.kafka.clients.consumer.internals.Fetcher.fetchedRecords(Fetcher.java:354)
at org.apache.kafka.clients.consumer.KafkaConsumer.pollOnce(KafkaConsumer.java:1000)
at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:938)

---

请帮我找到下面的自定义序列化程序和反序列化程序，用于case类User，User（name:String，id:Int）。将代码中的用户替换为案例类。它会起作用的

import java.io.{ObjectInputStream, ByteArrayInputStream}
import java.util

import org.apache.kafka.common.serialization.{Deserializer, Serializer}

class CustomDeserializer extends Deserializer[User]{

  override def configure(configs: util.Map[String,_],isKey: Boolean):Unit = {

  }
  override def deserialize(topic:String,bytes: Array[Byte]) = {
    val byteIn = new ByteArrayInputStream(bytes)
    val objIn = new ObjectInputStream(byteIn)
    val obj = objIn.readObject().asInstanceOf[User]
    byteIn.close()
    objIn.close()
    obj
  }
  override def close():Unit = {

  }

}

import java.io.{ObjectOutputStream, ByteArrayOutputStream}
import java.util
import org.apache.kafka.common.serialization.Serializer


class CustomSerializer extends Serializer[User]{

  override def configure(configs: util.Map[String,_],isKey: Boolean):Unit = {

  }


  override def serialize(topic:String, data:User):Array[Byte] = {
    try {
      val byteOut = new ByteArrayOutputStream()
      val objOut = new ObjectOutputStream(byteOut)
      objOut.writeObject(data)
      objOut.close()
      byteOut.close()
      byteOut.toByteArray
    }
    catch {
      case ex:Exception => throw new Exception(ex.getMessage)
    }
  }

  override def close():Unit = {

  }


}

---

你试过什么？你的要求是什么？你被困在哪里了？我找到了java示例，但在scala中没有。如果您知道使用scala编写示例，请不要共享您的反序列化程序需要一个对象，但消息是Array@MaheshChand Kandpal:获取由以下原因引起的错误：java.io.streamcorruptedeException:无效流头：@dhyanandrasingh在您共享代码之前，我无法帮助您。问这个问题并给我这个问题的URL。

import java.io.{ObjectInputStream, ByteArrayInputStream}
import java.util

import org.apache.kafka.common.serialization.{Deserializer, Serializer}

class CustomDeserializer extends Deserializer[User]{

  override def configure(configs: util.Map[String,_],isKey: Boolean):Unit = {

  }
  override def deserialize(topic:String,bytes: Array[Byte]) = {
    val byteIn = new ByteArrayInputStream(bytes)
    val objIn = new ObjectInputStream(byteIn)
    val obj = objIn.readObject().asInstanceOf[User]
    byteIn.close()
    objIn.close()
    obj
  }
  override def close():Unit = {

  }

}

import java.io.{ObjectOutputStream, ByteArrayOutputStream}
import java.util
import org.apache.kafka.common.serialization.Serializer


class CustomSerializer extends Serializer[User]{

  override def configure(configs: util.Map[String,_],isKey: Boolean):Unit = {

  }


  override def serialize(topic:String, data:User):Array[Byte] = {
    try {
      val byteOut = new ByteArrayOutputStream()
      val objOut = new ObjectOutputStream(byteOut)
      objOut.writeObject(data)
      objOut.close()
      byteOut.close()
      byteOut.toByteArray
    }
    catch {
      case ex:Exception => throw new Exception(ex.getMessage)
    }
  }

  override def close():Unit = {

  }


}