【Spark】SparkSession基础

SparkSession = SparkContext + HiveContext + StreamingContext + SQLContext

val conf = new SparkConf().setMaster("master").setAppName("appName1")
val sc = new SparkContext(conf)  //或者val sc = new SparkContext("master","appName1")

SparkConf一旦被设置，就不能被修改，存储setting的事ConcurrentHashMap