"No implicits found" 从 Case 类集合创建 Flink DataStream 时

Question

我正在尝试做一个 flink scala api hello world 但我无法复制从 https://www.slideshare.net/dataArtisans/apache-flink-datastream-api-basics/20

此处看到的开始教程片段

我尝试的副本是：

  val env = StreamExecutionEnvironment.getExecutionEnvironment
  case class Order(user: String, product: String, amount: Double, proctime: Int, rowtime: Int)

  def basic() = {
    val seq = (1 to 50).map { i => Order(s"User" + (i % 10).toString, "Product" + (i % 20), 2.0 * (4 * i +.5 * i * i -.1 * i * i * i), i * 10, i * 3) }
    val ds: DataStream[Order] = env.fromElements(seq:_*)

但是隐式不起作用，给出

Error:(21, 30) could not find implicit value for evidence parameter of type org.apache.flink.api.common.typeinfo.TypeInformation[com.blazedb.spark.FlinkDemo.Order]

这里需要修改什么？

Answer 1

随便做

import org.apache.flink.streaming.api.scala._

为了导入隐式TypeInformation[T]

https://github.com/apache/flink/blob/master/flink-scala/src/main/scala/org/apache/flink/api/scala/package.scala#L49

"No implicits found" 从 Case 类 集合创建 Flink DataStream 时

"No implicits found" when creating a Flink DataStream from a collection of Case Classes

scala

implicit

apache-flink

"No implicits found" 从 Case 类集合创建 Flink DataStream 时