Scala IntelliJ library import errors - scala

Question

I am new to scala and I am trying to import the following libraries in my build.sbt. When IntelliJ does an auto-update I get the following error:
Error while importing sbt project:
List([info] welcome to sbt 1.3.13 (Oracle Corporation Java 1.8.0_251)
[info] loading global plugins from C:\Users\diego\.sbt\1.0\plugins
[info] loading project definition from C:\Users\diego\development\Meetup\Stream-Processing\project
[info] loading settings for project stream-processing from build.sbt ...
[info] set current project to Stream-Processing (in build file:/C:/Users/diego/development/Meetup/Stream-Processing/)
[info] sbt server started at local:sbt-server-80d70f9339b81b4d026a
sbt:Stream-Processing>
[info] Defining Global / sbtStructureOptions, Global / sbtStructureOutputFile and 1 others.
[info] The new values will be used by cleanKeepGlobs
[info] Run `last` for details.
[info] Reapplying settings...
[info] set current project to Stream-Processing (in build file:/C:/Users/diego/development/Meetup/Stream-Processing/)
[info] Applying State transformations org.jetbrains.sbt.CreateTasks from C:/Users/diego/.IntelliJIdea2019.3/config/plugins/Scala/repo/org.jetbrains/sbt-structure-extractor/scala_2.12/sbt_1.0/2018.2.1+4-88400d3f/jars/sbt-structure-extractor.jar
[info] Reapplying settings...
[info] set current project to Stream-Processing (in build file:/C:/Users/diego/development/Meetup/Stream-Processing/)
[warn]
[warn] Note: Unresolved dependencies path:
[error] stack trace is suppressed; run 'last update' for the full output
[error] stack trace is suppressed; run 'last ssExtractDependencies' for the full output
[error] (update) sbt.librarymanagement.ResolveException: Error downloading org.apache.kafka:kafka-clients_2.11:2.3.1
[error] Not found
[error] Not found
[error] not found: C:\Users\diego\.ivy2\local\org.apache.kafka\kafka-clients_2.11\2.3.1\ivys\ivy.xml
[error] not found: https://repo1.maven.org/maven2/org/apache/kafka/kafka-clients_2.11/2.3.1/kafka-clients_2.11-2.3.1.pom
[error] (ssExtractDependencies) sbt.librarymanagement.ResolveException: Error downloading org.apache.kafka:kafka-clients_2.11:2.3.1
[error] Not found
[error] Not found
[error] not found: C:\Users\diego\.ivy2\local\org.apache.kafka\kafka-clients_2.11\2.3.1\ivys\ivy.xml
[error] not found: https://repo1.maven.org/maven2/org/apache/kafka/kafka-clients_2.11/2.3.1/kafka-clients_2.11-2.3.1.pom
[error] Total time: 2 s, completed Jun 28, 2020 12:11:24 PM
[info] shutting down sbt server)
This is my build.sbt file:
name := "Stream-Processing"
version := "1.0"
scalaVersion := "2.11.8"
libraryDependencies += "org.apache.spark" %% "spark-sql" % "2.4.4"
// https://mvnrepository.com/artifact/org.apache.spark/spark-sql-kafka-0-10_2.12
libraryDependencies += "org.apache.spark" %% "spark-sql-kafka-0-10" % "2.4.4"
// https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients
libraryDependencies += "org.apache.kafka" %% "kafka-clients" % "2.3.1"
// https://mvnrepository.com/artifact/mysql/mysql-connector-java
libraryDependencies += "mysql" % "mysql-connector-java" % "8.0.18"
// https://mvnrepository.com/artifact/org.mongodb.spark/mongo-spark-connector
libraryDependencies += "org.mongodb.spark" %% "mongo-spark-connector" % "2.4.1"
I made a Scala project just to make sure Spark works and my python project using Kafka works as well so I am sure it's not a spark/kafka problem. Any reason why I am getting that error?

Answer 1

Try removing one % before "kafka-clients":
libraryDependencies += "org.apache.kafka" % "kafka-clients" % "2.3.1"
The semantics of %% in SBT is that it appends the Scala version being used to the artifact name, so it becomes org.apache.kafka:kafka-clients_2.11:2.3.1 as the error message shows as well. Note the _2.11 suffix.
This is a nice shorthand for Scala libraries, but can get confusing for beginners, when used with Java libs.