illegal cyclic inheritance involving trait Iterable

Error:(17, 9) illegal cyclic inheritance involving trait Iterable
val resultDataSet: DataSet[(String, Int)] = inputDataSet
刚开始学习scala,idea老是出现这个问题,在网上看到可能是scala的sdk版本太新,但换了版本之后还是不行,有大佬能帮忙解决吗?
下面是代码

import org.apache.flink.api.scala.ExecutionEnvironment

import org.apache.flink.api.scala._
//批处理的WordCount
object WordCount {
def main(args: Array[String]): Unit = {
//创建一个批处理的执行环境
val env: ExecutionEnvironment = ExecutionEnvironment.getExecutionEnvironment

//从文件中读取数据
val inputPath: String = "D:\\Flink\\FlinkTutorial\\src\\main\\resources\\WordCount.txt"
val inputDataSet: DataSet[String] = env.readTextFile(inputPath)

//对数据进行转换处理统计,先分词,再按照word进行分组,最后进行聚合统计
val resultDataSet: DataSet[(String, Int)] = inputDataSet
  .flatMap(_.split(" "))
  .map((_,1))
  .groupBy(0)    //以第一个元素作为key,进行分组
  .sum(1)      //对所有数据的第二个元素求和

//打印输出
resultDataSet.print()

}
}