Spark source (. 1) arranged Spark

Write familiar with the first sentence of the Code

val conf = new SparkConf (). setAppName ( "WordCount")
Click SparkConf (), find

private val settings = new ConcurrentHashMap[String, String]()

All configurations are visible to map [String, String] defined

// i.e. loadDefaults to true ==
 DEF the this () = the this ( to true)
 //
IF(loadDefaults) {
　　// loading system default configuration
    loadFromSystemProperties (to false)
}

Private[Spark] DEF loadFromSystemProperties (Silent: Boolean): SparkConf ={
    / /. the any spark * the load system propertiesloads all spark * at the beginning of system attributes
    for((Key, value) <- Utils.getSystemPropertiesIFkey.startsWith ("Spark.")) {
      SET(Key, value, Silent)
    }
    the this
  }

  / ** the Set Configuration A variable.* / Set attributes themselves 
DEF SET (Key: String, value: String): SparkConf = {
     SET (Key, value, to false ) 
  }

// the code at the beginning of a call that is written in the method, which in turn calls the set method, to complete the configuration 
DEF setAppName (name: String): = {SparkConf 
  set ( "spark.app.name", name) 
}