元组复杂例子

def test4(): Unit = {
    val conf = new SparkConf().setAppName("WC").setMaster("local[2]")
    val sc = new SparkContext(conf)
    val arr = List(("Apache" -> "Spark"), ("Apache" -> "Kafka"), ("Oracle" -> "JAVA", "Oracle" -> "DB ORACLE", "Oracle" -> "Mysql"));
    val tmp = arr.foldLeft(mutable.ListBuffer[Tuple2[String,String]]())((m,i)=>{      

if (i.productArity > 2) {
        val it = i.productIterator
        while(it.hasNext){
          val t = it.next()
          m+=t.asInstanceOf[Tuple2[String,String]]
        }
          m
      } else {
        m += i.asInstanceOf[Tuple2[String,String]]
      }
    });

    tmp.foreach(println(_))
    val rdd1  = sc.makeRDD(tmp).groupByKey()
    println(rdd1.collect().toBuffer)
  }