From 48a9804b2ad89b3fb204c79f0dbadbcfea15d8dc Mon Sep 17 00:00:00 2001 From: cody koeninger Date: Tue, 8 Dec 2015 11:02:35 +0000 Subject: [SPARK-12103][STREAMING][KAFKA][DOC] document that K means Key and V … MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit …means Value Author: cody koeninger Closes #10132 from koeninger/SPARK-12103. --- .../apache/spark/streaming/kafka/KafkaUtils.scala | 61 ++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala index ad2fb8aa5f..fe57222052 100644 --- a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala +++ b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala @@ -51,6 +51,7 @@ object KafkaUtils { * in its own thread * @param storageLevel Storage level to use for storing the received objects * (default: StorageLevel.MEMORY_AND_DISK_SER_2) + * @return DStream of (Kafka message key, Kafka message value) */ def createStream( ssc: StreamingContext, @@ -74,6 +75,11 @@ object KafkaUtils { * @param topics Map of (topic_name -> numPartitions) to consume. Each partition is consumed * in its own thread. * @param storageLevel Storage level to use for storing the received objects + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam U type of Kafka message key decoder + * @tparam T type of Kafka message value decoder + * @return DStream of (Kafka message key, Kafka message value) */ def createStream[K: ClassTag, V: ClassTag, U <: Decoder[_]: ClassTag, T <: Decoder[_]: ClassTag]( ssc: StreamingContext, @@ -93,6 +99,7 @@ object KafkaUtils { * @param groupId The group id for this consumer * @param topics Map of (topic_name -> numPartitions) to consume. Each partition is consumed * in its own thread + * @return DStream of (Kafka message key, Kafka message value) */ def createStream( jssc: JavaStreamingContext, @@ -111,6 +118,7 @@ object KafkaUtils { * @param topics Map of (topic_name -> numPartitions) to consume. Each partition is consumed * in its own thread. * @param storageLevel RDD storage level. + * @return DStream of (Kafka message key, Kafka message value) */ def createStream( jssc: JavaStreamingContext, @@ -135,6 +143,11 @@ object KafkaUtils { * @param topics Map of (topic_name -> numPartitions) to consume. Each partition is consumed * in its own thread * @param storageLevel RDD storage level. + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam U type of Kafka message key decoder + * @tparam T type of Kafka message value decoder + * @return DStream of (Kafka message key, Kafka message value) */ def createStream[K, V, U <: Decoder[_], T <: Decoder[_]]( jssc: JavaStreamingContext, @@ -219,6 +232,11 @@ object KafkaUtils { * host1:port1,host2:port2 form. * @param offsetRanges Each OffsetRange in the batch corresponds to a * range of offsets for a given Kafka topic/partition + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @return RDD of (Kafka message key, Kafka message value) */ def createRDD[ K: ClassTag, @@ -251,6 +269,12 @@ object KafkaUtils { * @param leaders Kafka brokers for each TopicAndPartition in offsetRanges. May be an empty map, * in which case leaders will be looked up on the driver. * @param messageHandler Function for translating each message and metadata into the desired type + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @tparam R type returned by messageHandler + * @return RDD of R */ def createRDD[ K: ClassTag, @@ -288,6 +312,15 @@ object KafkaUtils { * host1:port1,host2:port2 form. * @param offsetRanges Each OffsetRange in the batch corresponds to a * range of offsets for a given Kafka topic/partition + * @param keyClass type of Kafka message key + * @param valueClass type of Kafka message value + * @param keyDecoderClass type of Kafka message key decoder + * @param valueDecoderClass type of Kafka message value decoder + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @return RDD of (Kafka message key, Kafka message value) */ def createRDD[K, V, KD <: Decoder[K], VD <: Decoder[V]]( jsc: JavaSparkContext, @@ -321,6 +354,12 @@ object KafkaUtils { * @param leaders Kafka brokers for each TopicAndPartition in offsetRanges. May be an empty map, * in which case leaders will be looked up on the driver. * @param messageHandler Function for translating each message and metadata into the desired type + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @tparam R type returned by messageHandler + * @return RDD of R */ def createRDD[K, V, KD <: Decoder[K], VD <: Decoder[V], R]( jsc: JavaSparkContext, @@ -373,6 +412,12 @@ object KafkaUtils { * @param fromOffsets Per-topic/partition Kafka offsets defining the (inclusive) * starting point of the stream * @param messageHandler Function for translating each message and metadata into the desired type + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @tparam R type returned by messageHandler + * @return DStream of R */ def createDirectStream[ K: ClassTag, @@ -419,6 +464,11 @@ object KafkaUtils { * If not starting from a checkpoint, "auto.offset.reset" may be set to "largest" or "smallest" * to determine where the stream starts (defaults to "largest") * @param topics Names of the topics to consume + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @return DStream of (Kafka message key, Kafka message value) */ def createDirectStream[ K: ClassTag, @@ -470,6 +520,12 @@ object KafkaUtils { * @param fromOffsets Per-topic/partition Kafka offsets defining the (inclusive) * starting point of the stream * @param messageHandler Function for translating each message and metadata into the desired type + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @tparam R type returned by messageHandler + * @return DStream of R */ def createDirectStream[K, V, KD <: Decoder[K], VD <: Decoder[V], R]( jssc: JavaStreamingContext, @@ -529,6 +585,11 @@ object KafkaUtils { * If not starting from a checkpoint, "auto.offset.reset" may be set to "largest" or "smallest" * to determine where the stream starts (defaults to "largest") * @param topics Names of the topics to consume + * @tparam K type of Kafka message key + * @tparam V type of Kafka message value + * @tparam KD type of Kafka message key decoder + * @tparam VD type of Kafka message value decoder + * @return DStream of (Kafka message key, Kafka message value) */ def createDirectStream[K, V, KD <: Decoder[K], VD <: Decoder[V]]( jssc: JavaStreamingContext, -- cgit v1.2.3