Executing Spark scala program after compilation - scala

Question

I have compiled Spark scala program on command line. But now I want to execute it. I dont want to use Maven or sbt.
the program .I have used the command to execute the
scala -cp ".:sparkDIrector/jars/*" wordcount
But I am getting this error
java.lang.NoSuchMethodError: scala.Predef$.refArrayOps([Ljava/lang/Object;)Lscala/collection/mutable/ArrayOps;
import org.apache.spark._
import org.apache.spark.SparkConf
/** Create a RDD of lines from a text file, and keep count of
* how often each word appears.
*/
object wordcount1 {
def main(args: Array[String]) {
// Set up a SparkContext named WordCount that runs locally using
// all available cores.
println("before conf")
val conf = new SparkConf().setAppName("WordCount")
conf.setMaster("local[*]")
val sc = new SparkContext(conf)
println("after the textfile")
// Create a RDD of lines of text in our book
val input = sc.textFile("book.txt")
println("after the textfile")
// Use flatMap to convert this into an rdd of each word in each line
val words = input.flatMap(line => line.split(' '))
// Convert these words to lowercase
val lowerCaseWords = words.map(word => word.toLowerCase())
// Count up the occurence of each unique word
println("before text file")
val wordCounts = lowerCaseWords.countByValue()
// Print the first 20 results
val sample = wordCounts.take(20)
for ((word, count) <- sample) {
println(word + " " + count)
}
sc.stop()
}
}
It is showing that the error is at location
val conf = new SparkConf().setAppName("WordCount").
Any help?

Answer 1

Starting from Spark 2.0 the entry point is the SparkSession:
import org.apache.spark.sql.SparkSession
val spark = SparkSession
.builder
.appName("App Name")
.getOrCreate()
Then you can access the SparkContext and read the file with:
spark.sparkContext().textFile(yourFileOrURL)
Remember to stop your session at the end:
spark.stop()
I suggest you to have a look at these examples: https://github.com/apache/spark/blob/master/examples/src/main/scala/org/apache/spark/examples
Then, to launch your application, you have to use spark-submit:
./bin/spark-submit \
--class <main-class> \
--master <master-url> \
--deploy-mode <deploy-mode> \
--conf <key>=<value> \
... # other options
<application-jar> \
[application-arguments]
In your case, it will be something like:
./bin/spark-submit \
--class wordcount1 \
--master local \
/path/to/your.jar