简单的wordcount

object Test16_CommonWordCount {
  def main(args: Array[String]): Unit = {
    val list = List(
      "hello",
      "hello world",
      "hello scala",
      "hello world",
      "hello scala",
      "hello java"
    )
    //1、对字符串进行切分，得到一个打散所有单词的列表
    val wordlist = list.flatMap(_.split(","))
    println(wordlist)

    //2、相同的单词进行分组
    val grouplist = wordlist.groupBy( word => word )
    println(grouplist)

    //3、对分组之后的list取长度，得到每个单词的个数
    val countMap = grouplist.map(kv => (kv._1, kv._2.length))

    //4、将map转换为list，排序取出前3
    val sortlist = countMap.toList
      .sortWith( _._2 > _._2 )
      .take(3).foreach(println)
  }
}