Solving Exception in thread “main” java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream

Question

I'm using Jetbrains IntelliJ IDEA with the Scala plugin and I'm trying to execute some code that uses Apache Spark. However whenever I try to run it, the code doesn't execute properly because of the exception

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream
    at org.apache.spark.SparkConf.loadFromSystemProperties(SparkConf.scala:76)
    at org.apache.spark.SparkConf.<init>(SparkConf.scala:71)
    at org.apache.spark.SparkConf.<init>(SparkConf.scala:58)
    at KMeans$.main(kmeans.scala:71)
    at KMeans.main(kmeans.scala)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FSDataInputStream
    at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 5 more

Running spark-shell from terminal doesn't give me any problems, the warning unable to load native-hadoop library for your platform doesn't appear to me. I've read some questions similar to mine, but in those cases they had problems with spark-shell or with cluster configuration.

Answer 1

I was using spark-core_2.12-2.4.3.jar without the dependencies. I solved the issue by adding spark-core library through Maven, which automatically added all the dependencies.