[SPARK-7799][SPARK-12786][STREAMING] Add "streaming-akka" project

Include the following changes:

1. Add "streaming-akka" project and org.apache.spark.streaming.akka.AkkaUtils for creating an actorStream
2. Remove "StreamingContext.actorStream" and "JavaStreamingContext.actorStream"
3. Update the ActorWordCount example and add the JavaActorWordCount example
4. Make "streaming-zeromq" depend on "streaming-akka" and update the codes accordingly

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #10744 from zsxwing/streaming-akka-2.

2 files changed, 15 insertions, 4 deletions

diff --git a/project/MimaExcludes.scala b/project/MimaExcludes.scala
index 6469201446..905fb4cd90 100644
--- a/project/MimaExcludes.scala
+++ b/project/MimaExcludes.scala
@@ -154,6 +154,16 @@ object MimaExcludes {
         ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.flume.sink.TransactionProcessor.org$apache$spark$streaming$flume$sink$Logging$$log_"),
         ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.flume.sink.TransactionProcessor.org$apache$spark$streaming$flume$sink$Logging$$log__=")
       ) ++ Seq(
+        // SPARK-7799 Add "streaming-akka" project
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.zeromq.ZeroMQUtils.createStream"),
+        ProblemFilters.exclude[IncompatibleMethTypeProblem]("org.apache.spark.streaming.zeromq.ZeroMQUtils.createStream"),
+        ProblemFilters.exclude[IncompatibleResultTypeProblem]("org.apache.spark.streaming.zeromq.ZeroMQUtils.createStream$default$6"),
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.zeromq.ZeroMQUtils.createStream$default$5"),
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.StreamingContext.actorStream$default$4"),
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.StreamingContext.actorStream$default$3"),
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.StreamingContext.actorStream"),
+        ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.streaming.api.java.JavaStreamingContext.actorStream")
+      ) ++ Seq(
         // SPARK-12847 Remove StreamingListenerBus and post all Streaming events to the same thread as Spark events
         ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.util.AsynchronousListenerBus$"),
         ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.util.AsynchronousListenerBus")
diff --git a/project/SparkBuild.scala b/project/SparkBuild.scala
index 06e561ae0d..3927b88fb0 100644
--- a/project/SparkBuild.scala
+++ b/project/SparkBuild.scala
@@ -35,11 +35,11 @@ object BuildCommons {
   private val buildLocation = file(".").getAbsoluteFile.getParentFile
 
   val allProjects@Seq(catalyst, core, graphx, hive, hiveThriftServer, mllib, repl,
-    sql, networkCommon, networkShuffle, streaming, streamingFlumeSink, streamingFlume, streamingKafka,
+    sql, networkCommon, networkShuffle, streaming, streamingFlumeSink, streamingFlume, streamingAkka, streamingKafka,
     streamingMqtt, streamingTwitter, streamingZeromq, launcher, unsafe, testTags) =
     Seq("catalyst", "core", "graphx", "hive", "hive-thriftserver", "mllib", "repl",
       "sql", "network-common", "network-shuffle", "streaming", "streaming-flume-sink",
-      "streaming-flume", "streaming-kafka", "streaming-mqtt", "streaming-twitter",
+      "streaming-flume", "streaming-akka", "streaming-kafka", "streaming-mqtt", "streaming-twitter",
       "streaming-zeromq", "launcher", "unsafe", "test-tags").map(ProjectRef(buildLocation, _))
 
   val optionallyEnabledProjects@Seq(yarn, java8Tests, sparkGangliaLgpl,
@@ -232,8 +232,9 @@ object SparkBuild extends PomBuild {
   /* Enable tests settings for all projects except examples, assembly and tools */
   (allProjects ++ optionallyEnabledProjects).foreach(enable(TestSettings.settings))
 
+  // TODO: remove streamingAkka from this list after 2.0.0
   allProjects.filterNot(x => Seq(spark, hive, hiveThriftServer, catalyst, repl,
-    networkCommon, networkShuffle, networkYarn, unsafe, testTags).contains(x)).foreach {
+    networkCommon, networkShuffle, networkYarn, unsafe, streamingAkka, testTags).contains(x)).foreach {
       x => enable(MimaBuild.mimaSettings(sparkHome, x))(x)
     }
 
@@ -649,7 +650,7 @@ object Unidoc {
       "-public",
       "-group", "Core Java API", packageList("api.java", "api.java.function"),
       "-group", "Spark Streaming", packageList(
-        "streaming.api.java", "streaming.flume", "streaming.kafka",
+        "streaming.api.java", "streaming.flume", "streaming.akka", "streaming.kafka",
         "streaming.mqtt", "streaming.twitter", "streaming.zeromq", "streaming.kinesis"
       ),
       "-group", "MLlib", packageList(