Bad Things On Code.

ClientBase.scala

// somewhere inside some cool framework

 val classpathEntries = Option(conf.getStrings(YarnConfiguration.YARN_APPLICATION_CLASSPATH)).
      getOrElse(getDefaultYarnApplicationClasspath())

// where

  def getDefaultYarnApplicationClasspath(): Array[String] = {
    try {
      val field = classOf[MRJobConfig].getField("DEFAULT_YARN_APPLICATION_CLASSPATH")
      field.get(null).asInstanceOf[Array[String]]
    } catch {
      case err: NoSuchFieldError => null     
      case err: NoSuchFieldException => null 
    }
  }
  
// O.o ... why? oh why? Just return Empty!