原始代码
object TransformTest {
def main(args: Array[String]): Unit = {
val env =
val stream: DataStreamSource[String] = ("src/main/resources/")
val value: DataStream[SensorReading] = stream
.map(a => {
val arr: Array[String] = (",")
new SensorReading(arr(0).trim, arr(1)., arr(2).)
})
val value1: DataStream[SensorReading] = value
.keyBy("id")
.reduce((a,b)=>new SensorReading(,+1,+10))
()
("tranform")
}
}
case class SensorReading(id:String,timestamp:Long,temperature:Double)
解决办法
样例类(实体类)中要有无参构造方法,应把SensorReading类修改如下形式
class SensorReading(){
var id:String=_
var timestamp:Long=_
var temperature:Double=_
def this(id1:String,timestamp1:Long,temperature1:Double){
this
id=id1
timestamp=timestamp1
temperature=temperature1
}
override def toString: String = id+"+"+timestamp+"+"+temperature
}