could not find implicit value for evidence parameter
<p>I am writing a simple word count flink job but I keep getting this error:</p>

<pre><code>could not find implicit value for evidence parameter of type org.apache.flink.api.common.typeinfo.TypeInformation[String]
[error]  .flatMap{_.toLowerCase.split("\\W+") filter {_.nonEmpty}}
</code></pre>

<p>I searched the net but could not get any comprehensible answer. </p>

<p>Here is my code:</p>

<pre><code>object Job {
  def main(args: Array[String]) {
    // set up the execution environment
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    val dataStream = env.readTextFile("file:///home/plivo/code/flink/scala/flinkstream/test/")

    val count = dataStream
                .flatMap{_.toLowerCase.split("\\W+") filter {_.nonEmpty}}
                .map{ (_,1) }
                .groupBy(0)
                .sum(1)


    dataStream.print()
    env.execute("Flink Scala API Skeleton")
    }
}
</code></pre>