K-V对的RDD遍历
val hashpartitionCounts: RDD[(String, Int)] = kvpartitionRDD.reduceByKey((x, y) => x + y)
hashpartitionCounts.foreach{ line=>
println("word="+line._1+" ,num="+line._2)
}
//下面的for和上面的一样结果
for (i <- hashpartitionCounts)
print("word="+i._1+" ,num="+i._2)
对数组RDD的遍历
//测试flatMap
val wordPairRDD:RDD[String] = lineRDD.flatMap(line => {
//将行转化为单词数组
val words: Array[String] = line.split(" ")
//单个单词数组 转化为相邻单词数组
for (i <- 0 until words.length - 1) yield words(i) + "-" + words(i + 1)
}
)
println("==========flatMap测试==========")
wordPairRDD.foreach(println)
其中存在的yield详解下
&nbs