Hi,      I am using CDH 5.9.1. I submitted a spark job which uses a jar compiled with spark 1.6.0. Got following exception :       Exception in thread "main" java.lang.AbstractMethodError         at org.apache.spark.Logging$class.log(Logging.scala:50)   So, tried to build that jar with spark 1.6.0-cdh5.9.1:     <dependency>       <groupId>org.apache.spark</groupId>       <artifactId>spark-core_2.10</artifactId>       <version>1.6.0-cdh5.9.1</version>     <scope>provided</scope>    </dependency>     It has 4 spark dependencies: spark-core, spark-catalyst, spark-hive and spark-sql. Getting following compilation error: [ERROR] error: bad symbolic reference. A signature in SQLContext.class refers to term runtime [INFO] in package scala.reflect which is not available. [INFO] It may be completely missing from the current classpath, or the version on [INFO] the classpath might be incompatible with the version used when compiling SQLContext.class. scala-library 2.10.4 was used. Same issue was seen even changing it to 2.10.5.   Thanks. ... View more