SPARK-3639 | Removed settings master in examples

This patch removes setting of master as local in Kinesis examples so that users can set it using submit-job.

Author: aniketbhatnagar <aniket.bhatnagar@gmail.com>

Closes #2536 from aniketbhatnagar/Kinesis-Examples-Master-Unset and squashes the following commits:

c9723ac [aniketbhatnagar] Merge remote-tracking branch 'origin/Kinesis-Examples-Master-Unset' into Kinesis-Examples-Master-Unset
fec8ead [aniketbhatnagar] SPARK-3639 | Removed settings master in examples
31cdc59 [aniketbhatnagar] SPARK-3639 | Removed settings master in examples

(cherry picked from commit d16e161)
Signed-off-by: Andrew Or <andrewor14@gmail.com>

extras/kinesis-asl/src/main/java/org/apache/spark/examples/streaming/JavaKinesisWordCountASL.java

@@ -71,6 +71,9 @@
  *            org.apache.spark.examples.streaming.JavaKinesisWordCountASL mySparkStream \
  *            https://kinesis.us-east-1.amazonaws.com
  *
+ * Note that number of workers/threads should be 1 more than the number of receivers.
+ * This leaves one thread available for actually processing the data.
+ *
  * There is a companion helper class called KinesisWordCountProducerASL which puts dummy data 
  *   onto the Kinesis stream. 
  * Usage instructions for KinesisWordCountProducerASL are provided in the class definition.
@@ -114,12 +117,8 @@ public static void main(String[] args) {
         /* In this example, we're going to create 1 Kinesis Worker/Receiver/DStream for each shard */ 
         int numStreams = numShards;
 
-        /* Must add 1 more thread than the number of receivers or the output won't show properly from the driver */
-        int numSparkThreads = numStreams + 1;
-
         /* Setup the Spark config. */
-        SparkConf sparkConfig = new SparkConf().setAppName("KinesisWordCount").setMaster(
-                "local[" + numSparkThreads + "]");
+        SparkConf sparkConfig = new SparkConf().setAppName("KinesisWordCount");
 
         /* Kinesis checkpoint interval.  Same as batchInterval for this example. */
         Duration checkpointInterval = batchInterval;

extras/kinesis-asl/src/main/scala/org/apache/spark/examples/streaming/KinesisWordCountASL.scala

@@ -65,6 +65,10 @@ import org.apache.log4j.Level
  *        org.apache.spark.examples.streaming.KinesisWordCountASL mySparkStream \
  *        https://kinesis.us-east-1.amazonaws.com
  *
+ * 
+ * Note that number of workers/threads should be 1 more than the number of receivers.
+ * This leaves one thread available for actually processing the data.
+ *
  * There is a companion helper class below called KinesisWordCountProducerASL which puts
  *   dummy data onto the Kinesis stream.
  * Usage instructions for KinesisWordCountProducerASL are provided in that class definition.
@@ -97,17 +101,10 @@ private object KinesisWordCountASL extends Logging {
     /* In this example, we're going to create 1 Kinesis Worker/Receiver/DStream for each shard. */
     val numStreams = numShards
 
-    /* 
-     *  numSparkThreads should be 1 more thread than the number of receivers.
-     *  This leaves one thread available for actually processing the data.
-     */
-    val numSparkThreads = numStreams + 1
-
     /* Setup the and SparkConfig and StreamingContext */
     /* Spark Streaming batch interval */
-    val batchInterval = Milliseconds(2000)    
+    val batchInterval = Milliseconds(2000)
     val sparkConfig = new SparkConf().setAppName("KinesisWordCount")
-      .setMaster(s"local[$numSparkThreads]")
     val ssc = new StreamingContext(sparkConfig, batchInterval)
 
     /* Kinesis checkpoint interval.  Same as batchInterval for this example. */