diff --git a/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeUtils.scala b/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeUtils.scala
index 095bfb0c73a9a..a65a9b921aafa 100644
--- a/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeUtils.scala
+++ b/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeUtils.scala
@@ -247,7 +247,7 @@ object FlumeUtils {
  * This is a helper class that wraps the methods in FlumeUtils into more Python-friendly class and
  * function so that it can be easily instantiated and called from Python's FlumeUtils.
  */
-private class FlumeUtilsPythonHelper {
+private[flume] class FlumeUtilsPythonHelper {
 
   def createStream(
       jssc: JavaStreamingContext,
diff --git a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/Broker.scala b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/Broker.scala
index 5a74febb4bd46..9159051ba06e4 100644
--- a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/Broker.scala
+++ b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/Broker.scala
@@ -20,11 +20,9 @@ package org.apache.spark.streaming.kafka
 import org.apache.spark.annotation.Experimental
 
 /**
- * :: Experimental ::
- * Represent the host and port info for a Kafka broker.
- * Differs from the Kafka project's internal kafka.cluster.Broker, which contains a server ID
+ * Represents the host and port info for a Kafka broker.
+ * Differs from the Kafka project's internal kafka.cluster.Broker, which contains a server ID.
  */
-@Experimental
 final class Broker private(
     /** Broker's hostname */
     val host: String,
diff --git a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
index b608b75952721..79a9db4291bef 100644
--- a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
+++ b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
@@ -20,9 +20,8 @@ package org.apache.spark.streaming.kafka
 import java.io.File
 import java.lang.{Integer => JInt}
 import java.net.InetSocketAddress
-import java.util.{Map => JMap}
-import java.util.Properties
 import java.util.concurrent.TimeoutException
+import java.util.{Map => JMap, Properties}
 
 import scala.annotation.tailrec
 import scala.language.postfixOps
@@ -30,17 +29,16 @@ import scala.util.control.NonFatal
 
 import kafka.admin.AdminUtils
 import kafka.api.Request
-import kafka.common.TopicAndPartition
 import kafka.producer.{KeyedMessage, Producer, ProducerConfig}
 import kafka.serializer.StringEncoder
 import kafka.server.{KafkaConfig, KafkaServer}
 import kafka.utils.{ZKStringSerializer, ZkUtils}
-import org.apache.zookeeper.server.{NIOServerCnxnFactory, ZooKeeperServer}
 import org.I0Itec.zkclient.ZkClient
+import org.apache.zookeeper.server.{NIOServerCnxnFactory, ZooKeeperServer}
 
-import org.apache.spark.{Logging, SparkConf}
 import org.apache.spark.streaming.Time
 import org.apache.spark.util.Utils
+import org.apache.spark.{Logging, SparkConf}
 
 /**
  * This is a helper class for Kafka test suites. This has the functionality to set up
@@ -48,7 +46,7 @@ import org.apache.spark.util.Utils
  *
  * The reason to put Kafka test utility class in src is to test Python related Kafka APIs.
  */
-private class KafkaTestUtils extends Logging {
+private[kafka] class KafkaTestUtils extends Logging {
 
   // Zookeeper related configurations
   private val zkHost = "localhost"
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 f3b01bd60b178..388dbb8184106 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
@@ -17,29 +17,25 @@
 
 package org.apache.spark.streaming.kafka
 
-import java.lang.{Integer => JInt}
-import java.lang.{Long => JLong}
-import java.util.{Map => JMap}
-import java.util.{Set => JSet}
-import java.util.{List => JList}
+import java.lang.{Integer => JInt, Long => JLong}
+import java.util.{List => JList, Map => JMap, Set => JSet}
 
-import scala.reflect.ClassTag
 import scala.collection.JavaConversions._
+import scala.reflect.ClassTag
 
 import kafka.common.TopicAndPartition
 import kafka.message.MessageAndMetadata
-import kafka.serializer.{DefaultDecoder, Decoder, StringDecoder}
+import kafka.serializer.{Decoder, DefaultDecoder, StringDecoder}
 
 import org.apache.spark.api.java.function.{Function => JFunction}
-import org.apache.spark.streaming.util.WriteAheadLogUtils
-import org.apache.spark.{SparkContext, SparkException}
-import org.apache.spark.annotation.Experimental
+import org.apache.spark.api.java.{JavaPairRDD, JavaRDD, JavaSparkContext}
 import org.apache.spark.rdd.RDD
 import org.apache.spark.storage.StorageLevel
 import org.apache.spark.streaming.StreamingContext
-import org.apache.spark.streaming.api.java.{JavaPairInputDStream, JavaInputDStream, JavaPairReceiverInputDStream, JavaStreamingContext}
+import org.apache.spark.streaming.api.java.{JavaInputDStream, JavaPairInputDStream, JavaPairReceiverInputDStream, JavaStreamingContext}
 import org.apache.spark.streaming.dstream.{InputDStream, ReceiverInputDStream}
-import org.apache.spark.api.java.{JavaSparkContext, JavaPairRDD, JavaRDD}
+import org.apache.spark.streaming.util.WriteAheadLogUtils
+import org.apache.spark.{SparkContext, SparkException}
 
 object KafkaUtils {
   /**
@@ -196,7 +192,6 @@ object KafkaUtils {
    * @param offsetRanges Each OffsetRange in the batch corresponds to a
    *   range of offsets for a given Kafka topic/partition
    */
-  @Experimental
   def createRDD[
     K: ClassTag,
     V: ClassTag,
@@ -214,7 +209,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create a RDD from Kafka using offset ranges for each topic and partition. This allows you
    * specify the Kafka leader to connect to (to optimize fetching) and access the message as well
    * as the metadata.
@@ -230,7 +224,6 @@ object KafkaUtils {
    *   in which case leaders will be looked up on the driver.
    * @param messageHandler Function for translating each message and metadata into the desired type
    */
-  @Experimental
   def createRDD[
     K: ClassTag,
     V: ClassTag,
@@ -268,7 +261,6 @@ object KafkaUtils {
    * @param offsetRanges Each OffsetRange in the batch corresponds to a
    *   range of offsets for a given Kafka topic/partition
    */
-  @Experimental
   def createRDD[K, V, KD <: Decoder[K], VD <: Decoder[V]](
       jsc: JavaSparkContext,
       keyClass: Class[K],
@@ -287,7 +279,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create a RDD from Kafka using offset ranges for each topic and partition. This allows you
    * specify the Kafka leader to connect to (to optimize fetching) and access the message as well
    * as the metadata.
@@ -303,7 +294,6 @@ object KafkaUtils {
    *   in which case leaders will be looked up on the driver.
    * @param messageHandler Function for translating each message and metadata into the desired type
    */
-  @Experimental
   def createRDD[K, V, KD <: Decoder[K], VD <: Decoder[V], R](
       jsc: JavaSparkContext,
       keyClass: Class[K],
@@ -327,7 +317,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create an input stream that directly pulls messages from Kafka Brokers
    * without using any receiver. This stream can guarantee that each message
    * from Kafka is included in transformations exactly once (see points below).
@@ -357,7 +346,6 @@ object KafkaUtils {
    *    starting point of the stream
    * @param messageHandler Function for translating each message and metadata into the desired type
    */
-  @Experimental
   def createDirectStream[
     K: ClassTag,
     V: ClassTag,
@@ -375,7 +363,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create an input stream that directly pulls messages from Kafka Brokers
    * without using any receiver. This stream can guarantee that each message
    * from Kafka is included in transformations exactly once (see points below).
@@ -405,7 +392,6 @@ object KafkaUtils {
    *   to determine where the stream starts (defaults to "largest")
    * @param topics Names of the topics to consume
    */
-  @Experimental
   def createDirectStream[
     K: ClassTag,
     V: ClassTag,
@@ -437,7 +423,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create an input stream that directly pulls messages from Kafka Brokers
    * without using any receiver. This stream can guarantee that each message
    * from Kafka is included in transformations exactly once (see points below).
@@ -472,7 +457,6 @@ object KafkaUtils {
    *    starting point of the stream
    * @param messageHandler Function for translating each message and metadata into the desired type
    */
-  @Experimental
   def createDirectStream[K, V, KD <: Decoder[K], VD <: Decoder[V], R](
       jssc: JavaStreamingContext,
       keyClass: Class[K],
@@ -499,7 +483,6 @@ object KafkaUtils {
   }
 
   /**
-   * :: Experimental ::
    * Create an input stream that directly pulls messages from Kafka Brokers
    * without using any receiver. This stream can guarantee that each message
    * from Kafka is included in transformations exactly once (see points below).
@@ -533,7 +516,6 @@ object KafkaUtils {
    *   to determine where the stream starts (defaults to "largest")
    * @param topics Names of the topics to consume
    */
-  @Experimental
   def createDirectStream[K, V, KD <: Decoder[K], VD <: Decoder[V]](
       jssc: JavaStreamingContext,
       keyClass: Class[K],
@@ -564,7 +546,7 @@ object KafkaUtils {
  * classOf[KafkaUtilsPythonHelper].newInstance(), and the createStream()
  * takes care of known parameters instead of passing them from Python
  */
-private class KafkaUtilsPythonHelper {
+private[kafka] class KafkaUtilsPythonHelper {
   def createStream(
       jssc: JavaStreamingContext,
       kafkaParams: JMap[String, String],
diff --git a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/OffsetRange.scala b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/OffsetRange.scala
index 2f8981d4898bd..8a5f371494511 100644
--- a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/OffsetRange.scala
+++ b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/OffsetRange.scala
@@ -19,10 +19,7 @@ package org.apache.spark.streaming.kafka
 
 import kafka.common.TopicAndPartition
 
-import org.apache.spark.annotation.Experimental
-
 /**
- * :: Experimental ::
  * Represents any object that has a collection of [[OffsetRange]]s. This can be used access the
  * offset ranges in RDDs generated by the direct Kafka DStream (see
  * [[KafkaUtils.createDirectStream()]]).
@@ -33,13 +30,11 @@ import org.apache.spark.annotation.Experimental
  *   }
  * }}}
  */
-@Experimental
 trait HasOffsetRanges {
   def offsetRanges: Array[OffsetRange]
 }
 
 /**
- * :: Experimental ::
  * Represents a range of offsets from a single Kafka TopicAndPartition. Instances of this class
  * can be created with `OffsetRange.create()`.
  * @param topic Kafka topic name
@@ -47,7 +42,6 @@ trait HasOffsetRanges {
  * @param fromOffset Inclusive starting offset
  * @param untilOffset Exclusive ending offset
  */
-@Experimental
 final class OffsetRange private(
     val topic: String,
     val partition: Int,
@@ -84,10 +78,8 @@ final class OffsetRange private(
 }
 
 /**
- * :: Experimental ::
  * Companion object the provides methods to create instances of [[OffsetRange]].
  */
-@Experimental
 object OffsetRange {
   def create(topic: String, partition: Int, fromOffset: Long, untilOffset: Long): OffsetRange =
     new OffsetRange(topic, partition, fromOffset, untilOffset)
diff --git a/external/mqtt/src/main/scala/org/apache/spark/streaming/mqtt/MQTTUtils.scala b/external/mqtt/src/main/scala/org/apache/spark/streaming/mqtt/MQTTUtils.scala
index 38a1114863d15..7b8d56d6faf2d 100644
--- a/external/mqtt/src/main/scala/org/apache/spark/streaming/mqtt/MQTTUtils.scala
+++ b/external/mqtt/src/main/scala/org/apache/spark/streaming/mqtt/MQTTUtils.scala
@@ -21,8 +21,8 @@ import scala.reflect.ClassTag
 
 import org.apache.spark.storage.StorageLevel
 import org.apache.spark.streaming.StreamingContext
-import org.apache.spark.streaming.api.java.{JavaReceiverInputDStream, JavaStreamingContext, JavaDStream}
-import org.apache.spark.streaming.dstream.{ReceiverInputDStream, DStream}
+import org.apache.spark.streaming.api.java.{JavaDStream, JavaReceiverInputDStream, JavaStreamingContext}
+import org.apache.spark.streaming.dstream.ReceiverInputDStream
 
 object MQTTUtils {
   /**
@@ -79,7 +79,7 @@ object MQTTUtils {
  * This is a helper class that wraps the methods in MQTTUtils into more Python-friendly class and
  * function so that it can be easily instantiated and called from Python's MQTTUtils.
  */
-private class MQTTUtilsPythonHelper {
+private[mqtt] class MQTTUtilsPythonHelper {
 
   def createStream(
       jssc: JavaStreamingContext,
diff --git a/external/mqtt/src/test/scala/org/apache/spark/streaming/mqtt/MQTTTestUtils.scala b/external/mqtt/src/test/scala/org/apache/spark/streaming/mqtt/MQTTTestUtils.scala
index 1a371b7008824..1618e2c088b70 100644
--- a/external/mqtt/src/test/scala/org/apache/spark/streaming/mqtt/MQTTTestUtils.scala
+++ b/external/mqtt/src/test/scala/org/apache/spark/streaming/mqtt/MQTTTestUtils.scala
@@ -33,7 +33,7 @@ import org.apache.spark.{Logging, SparkConf}
 /**
  * Share codes for Scala and Python unit tests
  */
-private class MQTTTestUtils extends Logging {
+private[mqtt] class MQTTTestUtils extends Logging {
 
   private val persistenceDir = Utils.createTempDir()
   private val brokerHost = "localhost"
diff --git a/extras/kinesis-asl/src/main/scala/org/apache/spark/streaming/kinesis/KinesisTestUtils.scala b/extras/kinesis-asl/src/main/scala/org/apache/spark/streaming/kinesis/KinesisTestUtils.scala
index 711aade182945..c8eec13ec7dc7 100644
--- a/extras/kinesis-asl/src/main/scala/org/apache/spark/streaming/kinesis/KinesisTestUtils.scala
+++ b/extras/kinesis-asl/src/main/scala/org/apache/spark/streaming/kinesis/KinesisTestUtils.scala
@@ -36,7 +36,7 @@ import org.apache.spark.Logging
 /**
  * Shared utility methods for performing Kinesis tests that actually transfer data
  */
-private class KinesisTestUtils extends Logging {
+private[kinesis] class KinesisTestUtils extends Logging {
 
   val endpointUrl = KinesisTestUtils.endpointUrl
   val regionName = RegionUtils.getRegionByEndpoint(endpointUrl).getName()
diff --git a/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLog.java b/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLog.java
index 8c0fdfa9c7478..3738fc1a235c2 100644
--- a/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLog.java
+++ b/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLog.java
@@ -21,6 +21,8 @@
 import java.util.Iterator;
 
 /**
+ * :: DeveloperApi ::
+ *
  * This abstract class represents a write ahead log (aka journal) that is used by Spark Streaming
  * to save the received data (by receivers) and associated metadata to a reliable storage, so that
  * they can be recovered after driver failures. See the Spark documentation for more information
diff --git a/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLogRecordHandle.java b/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLogRecordHandle.java
index 02324189b7822..662889e779fb2 100644
--- a/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLogRecordHandle.java
+++ b/streaming/src/main/java/org/apache/spark/streaming/util/WriteAheadLogRecordHandle.java
@@ -18,6 +18,8 @@
 package org.apache.spark.streaming.util;
 
 /**
+ * :: DeveloperApi ::
+ *
  * This abstract class represents a handle that refers to a record written in a
  * {@link org.apache.spark.streaming.util.WriteAheadLog WriteAheadLog}.
  * It must contain all the information necessary for the record to be read and returned by
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceivedBlockHandler.scala b/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceivedBlockHandler.scala
index c8dd6e06812dc..5f6c5b024085c 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceivedBlockHandler.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceivedBlockHandler.scala
@@ -222,7 +222,7 @@ private[streaming] object WriteAheadLogBasedBlockHandler {
 /**
  * A utility that will wrap the Iterator to get the count
  */
-private class CountingIterator[T](iterator: Iterator[T]) extends Iterator[T] {
+private[streaming] class CountingIterator[T](iterator: Iterator[T]) extends Iterator[T] {
    private var _count = 0
 
    private def isFullyConsumed: Boolean = !iterator.hasNext
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala b/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala
index aae3acf7aba3e..30d25a64e307a 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala
@@ -546,7 +546,7 @@ class ReceiverTracker(ssc: StreamingContext, skipReceiverLaunch: Boolean = false
  * Function to start the receiver on the worker node. Use a class instead of closure to avoid
  * the serialization issue.
  */
-private class StartReceiverFunc(
+private[streaming] class StartReceiverFunc(
     checkpointDirOption: Option[String],
     serializableHadoopConf: SerializableConfiguration)
   extends (Iterator[Receiver[_]] => Unit) with Serializable {
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/ui/BatchPage.scala b/streaming/src/main/scala/org/apache/spark/streaming/ui/BatchPage.scala
index 0c891662c264f..90d1b0fadecfc 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/ui/BatchPage.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/ui/BatchPage.scala
@@ -28,7 +28,7 @@ import org.apache.spark.ui.{UIUtils => SparkUIUtils, WebUIPage}
 import org.apache.spark.streaming.ui.StreamingJobProgressListener.{SparkJobId, OutputOpId}
 import org.apache.spark.ui.jobs.UIData.JobUIData
 
-private case class SparkJobIdWithUIData(sparkJobId: SparkJobId, jobUIData: Option[JobUIData])
+private[ui] case class SparkJobIdWithUIData(sparkJobId: SparkJobId, jobUIData: Option[JobUIData])
 
 private[ui] class BatchPage(parent: StreamingTab) extends WebUIPage("batch") {
   private val streamingListener = parent.listener