Implicit Scala & Spark UDF to covert a string to CamelCase

CustomStringUtils.scala

implicit class CustomStringUtils(s: String) {
  def toCamelCase = if (s == null) "" else {
      if (s.trim.isEmpty) s else s.split("[\\s+]").map{ word =>
         val first = Character.toUpperCase(word(0))
         val rest = word.replaceAll("^.(.*)", "$1").toLowerCase
         s"$first$rest"
    }.reduce(_+" "+_)
  }
}

import org.apache.spark.sql.functions.udf
val toCamelCase = udf((str: String) => str.toCamelCase)