Examples to create a Spark Session with Kryo

SparkSessionKryo.scala

import org.apache.spark.SparkConf
import org.apache.spark.sql.SparkSession

//create a spark session who works with Kryo.
object SparkSessionKryo {
    def getSparkSession: SparkSession = {
        val spark = SparkSession
            .builder
            .appName("my spark application name")
            .config(getConfig)
            .config("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
            // use this if you need to increment Kryo buffer size. Default 64k
            .config("spark.kryoserializer.buffer", "1024k") 
            // use this if you need to increment Kryo buffer max size. Default 64m
            .config("spark.kryoserializer.buffer.max", "1024m") 
            /*
            * Use this if you need to register all Kryo required classes. 
            * If it is false, you do not need register any class for Kryo, but it will increase your data size when the data is serializing.
            */
            .config("spark.kryo.registrationRequired", "true")
            .getOrCreate
    }

    private def getConfig = {
        val conf = new SparkConf()
        conf.registerKryoClasses(
          Array(
            classOf[scala.collection.mutable.WrappedArray.ofRef[_]],
            classOf[org.apache.spark.sql.types.StructType],
            classOf[Array[org.apache.spark.sql.types.StructType]],
            classOf[org.apache.spark.sql.types.StructField],
            classOf[Array[org.apache.spark.sql.types.StructField]],
            Class.forName("org.apache.spark.sql.types.StringType$"),
            Class.forName("org.apache.spark.sql.types.LongType$"),
            Class.forName("org.apache.spark.sql.types.BooleanType$"),
            Class.forName("org.apache.spark.sql.types.DoubleType$"),
            Class.forName("[[B"),
            classOf[org.apache.spark.sql.types.Metadata],
            classOf[org.apache.spark.sql.types.ArrayType],
            Class.forName("org.apache.spark.sql.execution.joins.UnsafeHashedRelation"),
            classOf[org.apache.spark.sql.catalyst.InternalRow],
            classOf[Array[org.apache.spark.sql.catalyst.InternalRow]],
            classOf[org.apache.spark.sql.catalyst.expressions.UnsafeRow],
            Class.forName("org.apache.spark.sql.execution.joins.LongHashedRelation"),
            Class.forName("org.apache.spark.sql.execution.joins.LongToUnsafeRowMap"),
            classOf[org.apache.spark.util.collection.BitSet],
            classOf[org.apache.spark.sql.types.DataType],
            classOf[Array[org.apache.spark.sql.types.DataType]],
            Class.forName("org.apache.spark.sql.types.NullType$"),
            Class.forName("org.apache.spark.sql.types.IntegerType$"),
            Class.forName("org.apache.spark.sql.types.TimestampType$"),
            Class.forName("org.apache.spark.sql.execution.datasources.FileFormatWriter$WriteTaskResult"),
            Class.forName("org.apache.spark.internal.io.FileCommitProtocol$TaskCommitMessage"),
            Class.forName("scala.collection.immutable.Set$EmptySet$"),
            Class.forName("scala.reflect.ClassTag$$anon$1"),
            Class.forName("java.lang.Class")
          )
        )
    }    
}

Need to return spark in getSparkSession

https://stackoverflow.com/questions/75806168/error-when-enabling-kyro-serializer-with-spark