Spark整合kafka0.10.0新特性(一)

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子曰:"温故而知新可以为师矣。" 学完长时间不使用不复习便会逐渐忘记,故做一下笔记!

Spark Streaming + Kafka Integration Guide (Kafka broker version 0.10.0 or higher)整合kafka0.10.0新特性(API都在实验中)。

 The Spark Streaming integration for Kafka 0.10和kafka0.8的Direct Stream approach非常相似,并行度Kafka分区和Spark分区的比例1:1,并且可以访问Kafka的偏移和元数据。然而,新的整合方案使用的是new Kafka consumer API 而不是 simple API,所以在使用过程中需要注意区别,这个版本的整合现在正处于experimental,因此API可能随着时间会有变化。

Linking

For Scala/Java applications using SBT/Maven project definitions, link your streaming application with the following artifact (see Linking sectionin the main programming guide for further information).

groupId = org.apache.sparkartifactId = spark-streaming-kafka-0-10_2.11version = 2.1.0

无论使用sbt还是maven,都需引入上面的坐标。


Creating a Direct Stream

注意导入包的路径是org.apache.spark.streaming.kafka010,切勿倒错包。

import org.apache.kafka.clients.consumer.ConsumerRecordimport org.apache.kafka.common.serialization.StringDeserializerimport org.apache.spark.streaming.kafka010._import org.apache.spark.streaming.kafka010.LocationStrategies.PreferConsistentimport org.apache.spark.streaming.kafka010.ConsumerStrategies.Subscribeval kafkaParams = Map[String, Object](     "bootstrap.servers" -> "localhost:9092,anotherhost:9092",  "key.deserializer" -> classOf[StringDeserializer],  "value.deserializer" -> classOf[StringDeserializer],  "group.id" -> "use_a_separate_group_id_for_each_stream",  "auto.offset.reset" -> "latest",  "enable.auto.commit" -> (false: java.lang.Boolean))val topics = Array("topicA", "topicB")val stream = KafkaUtils.createDirectStream[String, String](  streamingContext,//create entry point for all streaming functionality  PreferConsistent,//important feature:preferConsistent是一个方法,是consumer调度分区的位置策略  Subscribe[String, String](topics, kafkaParams)//is also import feature :Subscribe是consumer的消费策略)stream.map(record => (record.key, record.value))


重点解释一下 PreferConsistent方法,首先我们还是看一下PreferConsistent方法实现,源码如下:


package org.apache.spark.streaming.kafka010import java.{util => ju}import scala.collection.JavaConverters._import org.apache.kafka.common.TopicPartitionimport org.apache.spark.annotation.Experimentalimport org.apache.spark.streaming.kafka010.{LocationStrategies, LocationStrategy, PreferFixed}/**  *  :: Experimental ::  * Choice of how to schedule consumers for a given TopicPartition on an executor.  * See [[LocationStrategies]] to obtain instances.  * Kafka 0.10 consumers prefetch messages, so it's important for performance  * to keep cached consumers on appropriate executors, not recreate them for every partition.  * Choice of location is only a preference, not an absolute; partitions may be scheduled elsewhere.  * 实验性API:  * 在executor上consumer如何调度给定的TopicPartition,使用LocationStrategies获取调度策略实例  * Kafka 0.10的消费者可以预取消息,因此对于性能来说在适合的executors上缓存consumers是比较重要的,而不是对每一个分区  * 进行重新创建。对于分区位置的选择只是一个偏好,并非是绝对的。分区可能被调度到其他位置  *  *  */@Experimentalsealed abstract class LocationStrategy/**  * 使用PreferBrokers策略,必须是你的executors和kafka brokers在相同节点上。  */private case object PreferBrokers extends LocationStrategy/**  * 大多数情况下使用PreferConsistent需要一贯的将kafka的分区分布到所有的executors上  */private case object PreferConsistent extends LocationStrategy/**  * Use this to place particular TopicPartitions on particular hosts if your load is uneven.  * Any TopicPartition not specified in the map will use a consistent location.      * 默认情况如果分区加载的不均衡的话,可以使用这个策略:放置特定的分区到特定的主机上  * 任何TopicPartition没有和hosts映射的TopicPartition将会使用consistent location(就是安置到所有executor)  *  * 参数Map:就是TopicPartition和主机地址的映射  */private case class PreferFixed(hostMap: ju.Map[TopicPartition, String]) extends LocationStrategy/**  * :: Experimental :: object to obtain instances of [[LocationStrategy]]  *  */@Experimentalobject LocationStrategies {  /**    *  :: Experimental ::    * Use this only if your executors are on the same nodes as your Kafka brokers.    */  @Experimental  def PreferBrokers: LocationStrategy =  org.apache.spark.streaming.kafka010.PreferBrokers  /**    *  :: Experimental ::    * Use this in most cases, it will consistently distribute partitions across all executors.    */  @Experimental  def PreferConsistent: LocationStrategy =  org.apache.spark.streaming.kafka010.PreferConsistent  /**    *  :: Experimental ::    * Use this to place particular TopicPartitions on particular hosts if your load is uneven.    * Any TopicPartition not specified in the map will use a consistent location.    * 两个方法就是Map类型不一样而已,一个是Scala Map 另一个是Java Map    *    */  @Experimental  def PreferFixed(hostMap: collection.Map[TopicPartition, String]): LocationStrategy =  new PreferFixed(new ju.HashMap[TopicPartition, String](hostMap.asJava))  /**    *  :: Experimental ::    * Use this to place particular TopicPartitions on particular hosts if your load is uneven.    * Any TopicPartition not specified in the map will use a consistent location.    */  @Experimental  def PreferFixed(hostMap: ju.Map[TopicPartition, String]): LocationStrategy =  new PreferFixed(hostMap)}

接下来学习一下Subscribe,上面Subscribe是伴生对象ConsumerStrategies的一个静态方法,ConsumerStrategies可以说是consumer消费策略的一个工厂。
接下来看一下 ConsumerStrategy,重点部门见源码注释, 源码如下:
package org.apache.spark.streaming.kafka010import java.{ lang => jl, util => ju }import scala.collection.JavaConverters._import org.apache.kafka.clients.consumer._import org.apache.kafka.clients.consumer.internals.NoOpConsumerRebalanceListenerimport org.apache.kafka.common.TopicPartitionimport org.apache.spark.annotation.Experimentalimport org.apache.spark.internal.Logging/**  * :: Experimental ::  * Choice of how to create and configure underlying Kafka Consumers on driver and executors.  * See [[ConsumerStrategies]] to obtain instances.  * Kafka 0.10 consumers can require additional, sometimes complex, setup after object  *  instantiation. This interface encapsulates that process, and allows it to be checkpointed.  * @tparam K type of Kafka message key  * @tparam V type of Kafka message value  *  * 选择如何创建和配置在Driver和Executor上的Kafka Consumer实例,使用ConsumerStrategies获取策略实例  * Kafka 0.10 consumers 在对象被实例化之后需要额外的配置,有时候比较复杂,这个接口封装了那些过程  * 并允许实例被checkpointed  *  */@Experimentalabstract class ConsumerStrategy[K, V] {  /**    * Kafka <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on executors. Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    *配置参数会在executors上被使用,需要设置bootstrap.servers指定Kafka的broker的主机和端口    *    */  def executorKafkaParams: ju.Map[String, Object]  /**    * Must return a fully configured Kafka Consumer, including subscribed or assigned topics.    * See <a href="http://kafka.apache.org/documentation.html#newconsumerapi">Kafka docs</a>.    * This consumer will be used on the driver to query for offsets only, not messages.    * The consumer must be returned in a state that it is safe to call poll(0) on.    * @param currentOffsets A map from TopicPartition to offset, indicating how far the driver    * has successfully read.  Will be empty on initial start, possibly non-empty on restart from    * checkpoint.    *返回一个必须是fully配置的Kafka Consumer,消费策略可以是subscribed或者assigned    * consumer将会在driver上使用查询偏移而不是查询消息    * 返回的consumer状态必须是安全的调用poll(0)方法    * currentOffsets参数是一个TopicPartition到offset的映射map,可以标示:    * driver已经成功读取多少信息,第一次启动时候可能是empty,在checkpoint中restart不为空    *    */  def onStart(currentOffsets: ju.Map[TopicPartition, jl.Long]): Consumer[K, V]}/**  * Subscribe to a collection of topics.  * @param topics collection of topics to subscribe  * @param kafkaParams Kafka  * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">  * configuration parameters</a> to be used on driver. The same params will be used on executors,  * with minor automatic modifications applied.  *  Requires "bootstrap.servers" to be set  * with Kafka broker(s) specified in host1:port1,host2:port2 form.  * @param offsets: offsets to begin at on initial startup.  If no offset is given for a  * TopicPartition, the committed offset (if applicable) or kafka param  * auto.offset.reset will be used.  *  * 订阅一组topic消息  *kafkaParams参数:  *配置参数将会在driver上使用,并且相同参数也会发送到executor上使用,在executor上可能略微的配置修改  *通知需要设置bootstrap.servers指定broker  *  *offsets参数:  * offsets伴随着startup开始,如果对于TopicPartition没有指定offset,  * 提交的offset或auto.offset.reset将会被使用  *  *  */private case class Subscribe[K, V](                                    topics: ju.Collection[jl.String],                                    kafkaParams: ju.Map[String, Object],                                    offsets: ju.Map[TopicPartition, jl.Long]                                  ) extends ConsumerStrategy[K, V] with Logging {  /**    *继承至ConsumerStrategy的方法,获取配置参数    *    * @return    */  def executorKafkaParams: ju.Map[String, Object] = kafkaParams  /**    *    *  继承至ConsumerStrategy的方法,用于创建Consumer    * @return    */  def onStart(currentOffsets: ju.Map[TopicPartition, jl.Long]): Consumer[K, V] = {    val consumer = new KafkaConsumer[K, V](kafkaParams)    consumer.subscribe(topics)    val toSeek = if (currentOffsets.isEmpty) {      offsets    } else {      currentOffsets    }    if (!toSeek.isEmpty) {      // work around KAFKA-3370 when reset is none      // poll will throw if no position, i.e. auto offset reset none and no explicit position      // but cant seek to a position before poll, because poll is what gets subscription partitions      // So, poll, suppress the first exception, then seek      val aor = kafkaParams.get(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG)      val shouldSuppress = aor != null && aor.asInstanceOf[String].toUpperCase == "NONE"      try {        consumer.poll(0)      } catch {        case x: NoOffsetForPartitionException if shouldSuppress =>          logWarning("Catching NoOffsetForPartitionException since " +            ConsumerConfig.AUTO_OFFSET_RESET_CONFIG + " is none.  See KAFKA-3370")      }      toSeek.asScala.foreach { case (topicPartition, offset) =>        consumer.seek(topicPartition, offset)      }      // we've called poll, we must pause or next poll may consume messages and set position      consumer.pause(consumer.assignment())    }    consumer  }}/**  * Subscribe to all topics matching specified pattern to get dynamically assigned partitions.  * The pattern matching will be done periodically against topics existing at the time of check.  * @param pattern pattern to subscribe to  * @param kafkaParams Kafka  * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">  * configuration parameters</a> to be used on driver. The same params will be used on executors,  * with minor automatic modifications applied.  *  Requires "bootstrap.servers" to be set  * with Kafka broker(s) specified in host1:port1,host2:port2 form.  * @param offsets: offsets to begin at on initial startup.  If no offset is given for a  * TopicPartition, the committed offset (if applicable) or kafka param  * auto.offset.reset will be used.  *  *  SubscribePattern是订阅所有匹配正则表达式模式的topic的数据  *  topic模式匹配将会周期性的进行匹配,而不是在检查已存在的topic时候进行模式匹配  *  *  kafkaParams参数:  *配置参数将会在driver上使用,并且相同参数也会发送到executor上使用,在executor上可能略微的配置修改  *通知需要设置bootstrap.servers指定broker  *  *offsets参数:  * offsets伴随着startup开始,如果对于TopicPartition没有指定offset,  * 提交的offset或auto.offset.reset将会被使用  *  *  */private case class SubscribePattern[K, V](                                           pattern: ju.regex.Pattern,                                           kafkaParams: ju.Map[String, Object],                                           offsets: ju.Map[TopicPartition, jl.Long]                                         ) extends ConsumerStrategy[K, V] with Logging {  def executorKafkaParams: ju.Map[String, Object] = kafkaParams  def onStart(currentOffsets: ju.Map[TopicPartition, jl.Long]): Consumer[K, V] = {    val consumer = new KafkaConsumer[K, V](kafkaParams)    consumer.subscribe(pattern, new NoOpConsumerRebalanceListener())    val toSeek = if (currentOffsets.isEmpty) {      offsets    } else {      currentOffsets    }    if (!toSeek.isEmpty) {      // work around KAFKA-3370 when reset is none, see explanation in Subscribe above      val aor = kafkaParams.get(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG)      val shouldSuppress = aor != null && aor.asInstanceOf[String].toUpperCase == "NONE"      try {        consumer.poll(0)      } catch {        case x: NoOffsetForPartitionException if shouldSuppress =>          logWarning("Catching NoOffsetForPartitionException since " +            ConsumerConfig.AUTO_OFFSET_RESET_CONFIG + " is none.  See KAFKA-3370")      }      toSeek.asScala.foreach { case (topicPartition, offset) =>        consumer.seek(topicPartition, offset)      }      // we've called poll, we must pause or next poll may consume messages and set position      consumer.pause(consumer.assignment())    }    consumer  }}/**  * Assign a fixed collection of TopicPartitions  * @param topicPartitions collection of TopicPartitions to assign  * @param kafkaParams Kafka  * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">  * configuration parameters</a> to be used on driver. The same params will be used on executors,  * with minor automatic modifications applied.  *  Requires "bootstrap.servers" to be set  * with Kafka broker(s) specified in host1:port1,host2:port2 form.  * @param offsets: offsets to begin at on initial startup.  If no offset is given for a  * TopicPartition, the committed offset (if applicable) or kafka param  * auto.offset.reset will be used.  *  *  订阅一个固定数目的TopicPartitions  * kafkaParams参数:  *配置参数将会在driver上使用,并且相同参数也会发送到executor上使用,在executor上可能略微的配置修改  *通知需要设置bootstrap.servers指定broker  *  *offsets参数:  * offsets伴随着startup开始,如果对于TopicPartition没有指定offset,  * 提交的offset或auto.offset.reset将会被使用  *  *  *  */private case class Assign[K, V](                                 topicPartitions: ju.Collection[TopicPartition],                                 kafkaParams: ju.Map[String, Object],                                 offsets: ju.Map[TopicPartition, jl.Long]                               ) extends ConsumerStrategy[K, V] {  def executorKafkaParams: ju.Map[String, Object] = kafkaParams  def onStart(currentOffsets: ju.Map[TopicPartition, jl.Long]): Consumer[K, V] = {    val consumer = new KafkaConsumer[K, V](kafkaParams)    consumer.assign(topicPartitions)    val toSeek = if (currentOffsets.isEmpty) {      offsets    } else {      currentOffsets    }    if (!toSeek.isEmpty) {      // this doesn't need a KAFKA-3370 workaround, because partitions are known, no poll needed      toSeek.asScala.foreach { case (topicPartition, offset) =>        consumer.seek(topicPartition, offset)      }    }    consumer  }}/**  * :: Experimental ::  * object for obtaining instances of [[ConsumerStrategy]]  *  * 这个是订阅策略的工厂方法:用于实例化策略的  *  *  *  */@Experimentalobject ConsumerStrategies {  /**    *  :: Experimental ::    * Subscribe to a collection of topics.    * @param topics collection of topics to subscribe    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def Subscribe[K, V](                       topics: Iterable[jl.String],                       kafkaParams: collection.Map[String, Object],                       offsets: collection.Map[TopicPartition, Long]): ConsumerStrategy[K, V] = {    new Subscribe[K, V](      new ju.ArrayList(topics.asJavaCollection),      new ju.HashMap[String, Object](kafkaParams.asJava),      new ju.HashMap[TopicPartition, jl.Long](offsets.mapValues(l => new jl.Long(l)).asJava))  }  /**    *  :: Experimental ::    * Subscribe to a collection of topics.    * @param topics collection of topics to subscribe    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def Subscribe[K, V](                       topics: Iterable[jl.String],                       kafkaParams: collection.Map[String, Object]): ConsumerStrategy[K, V] = {    new Subscribe[K, V](      new ju.ArrayList(topics.asJavaCollection),      new ju.HashMap[String, Object](kafkaParams.asJava),      ju.Collections.emptyMap[TopicPartition, jl.Long]())  }  /**    *  :: Experimental ::    * Subscribe to a collection of topics.    * @param topics collection of topics to subscribe    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def Subscribe[K, V](                       topics: ju.Collection[jl.String],                       kafkaParams: ju.Map[String, Object],                       offsets: ju.Map[TopicPartition, jl.Long]): ConsumerStrategy[K, V] = {    new Subscribe[K, V](topics, kafkaParams, offsets)  }  /**    *  :: Experimental ::    * Subscribe to a collection of topics.    * @param topics collection of topics to subscribe    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def Subscribe[K, V](                       topics: ju.Collection[jl.String],                       kafkaParams: ju.Map[String, Object]): ConsumerStrategy[K, V] = {    new Subscribe[K, V](topics, kafkaParams, ju.Collections.emptyMap[TopicPartition, jl.Long]())  }  /** :: Experimental ::    * Subscribe to all topics matching specified pattern to get dynamically assigned partitions.    * The pattern matching will be done periodically against topics existing at the time of check.    * @param pattern pattern to subscribe to    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def SubscribePattern[K, V](                              pattern: ju.regex.Pattern,                              kafkaParams: collection.Map[String, Object],                              offsets: collection.Map[TopicPartition, Long]): ConsumerStrategy[K, V] = {    new SubscribePattern[K, V](      pattern,      new ju.HashMap[String, Object](kafkaParams.asJava),      new ju.HashMap[TopicPartition, jl.Long](offsets.mapValues(l => new jl.Long(l)).asJava))  }  /** :: Experimental ::    * Subscribe to all topics matching specified pattern to get dynamically assigned partitions.    * The pattern matching will be done periodically against topics existing at the time of check.    * @param pattern pattern to subscribe to    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def SubscribePattern[K, V](                              pattern: ju.regex.Pattern,                              kafkaParams: collection.Map[String, Object]): ConsumerStrategy[K, V] = {    new SubscribePattern[K, V](      pattern,      new ju.HashMap[String, Object](kafkaParams.asJava),      ju.Collections.emptyMap[TopicPartition, jl.Long]())  }  /** :: Experimental ::    * Subscribe to all topics matching specified pattern to get dynamically assigned partitions.    * The pattern matching will be done periodically against topics existing at the time of check.    * @param pattern pattern to subscribe to    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def SubscribePattern[K, V](                              pattern: ju.regex.Pattern,                              kafkaParams: ju.Map[String, Object],                              offsets: ju.Map[TopicPartition, jl.Long]): ConsumerStrategy[K, V] = {    new SubscribePattern[K, V](pattern, kafkaParams, offsets)  }  /** :: Experimental ::    * Subscribe to all topics matching specified pattern to get dynamically assigned partitions.    * The pattern matching will be done periodically against topics existing at the time of check.    * @param pattern pattern to subscribe to    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def SubscribePattern[K, V](                              pattern: ju.regex.Pattern,                              kafkaParams: ju.Map[String, Object]): ConsumerStrategy[K, V] = {    new SubscribePattern[K, V](      pattern,      kafkaParams,      ju.Collections.emptyMap[TopicPartition, jl.Long]())  }  /**    *  :: Experimental ::    * Assign a fixed collection of TopicPartitions    * @param topicPartitions collection of TopicPartitions to assign    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def Assign[K, V](                    topicPartitions: Iterable[TopicPartition],                    kafkaParams: collection.Map[String, Object],                    offsets: collection.Map[TopicPartition, Long]): ConsumerStrategy[K, V] = {    new Assign[K, V](      new ju.ArrayList(topicPartitions.asJavaCollection),      new ju.HashMap[String, Object](kafkaParams.asJava),      new ju.HashMap[TopicPartition, jl.Long](offsets.mapValues(l => new jl.Long(l)).asJava))  }  /**    *  :: Experimental ::    * Assign a fixed collection of TopicPartitions    * @param topicPartitions collection of TopicPartitions to assign    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def Assign[K, V](                    topicPartitions: Iterable[TopicPartition],                    kafkaParams: collection.Map[String, Object]): ConsumerStrategy[K, V] = {    new Assign[K, V](      new ju.ArrayList(topicPartitions.asJavaCollection),      new ju.HashMap[String, Object](kafkaParams.asJava),      ju.Collections.emptyMap[TopicPartition, jl.Long]())  }  /**    *  :: Experimental ::    * Assign a fixed collection of TopicPartitions    * @param topicPartitions collection of TopicPartitions to assign    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    * @param offsets: offsets to begin at on initial startup.  If no offset is given for a    * TopicPartition, the committed offset (if applicable) or kafka param    * auto.offset.reset will be used.    */  @Experimental  def Assign[K, V](                    topicPartitions: ju.Collection[TopicPartition],                    kafkaParams: ju.Map[String, Object],                    offsets: ju.Map[TopicPartition, jl.Long]): ConsumerStrategy[K, V] = {    new Assign[K, V](topicPartitions, kafkaParams, offsets)  }  /**    *  :: Experimental ::    * Assign a fixed collection of TopicPartitions    * @param topicPartitions collection of TopicPartitions to assign    * @param kafkaParams Kafka    * <a href="http://kafka.apache.org/documentation.html#newconsumerconfigs">    * configuration parameters</a> to be used on driver. The same params will be used on executors,    * with minor automatic modifications applied.    *  Requires "bootstrap.servers" to be set    * with Kafka broker(s) specified in host1:port1,host2:port2 form.    */  @Experimental  def Assign[K, V](                    topicPartitions: ju.Collection[TopicPartition],                    kafkaParams: ju.Map[String, Object]): ConsumerStrategy[K, V] = {    new Assign[K, V](      topicPartitions,      kafkaParams,      ju.Collections.emptyMap[TopicPartition, jl.Long]())  }}


本文到此结束,其余见Spark整合kafka0.10.0新特性(二)
补充:由于csdn博客编辑器偶尔出现对java代码排版出错问题,所以为了避免博文写的太长出错前功尽弃,所以将拆分多个博文讲解。


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