3

我在下面有交易者

val transactor: Resource[IO, HikariTransactor[IO]] =
    for {
      ce <- ExecutionContexts.fixedThreadPool[IO](32) // our connect EC
      be <- Blocker[IO] // our blocking EC
      xa <- HikariTransactor.newHikariTransactor[IO](
        "com.mysql.cj.jdbc.Driver",
        "jdbc:mysql://localhost:3306/ems",
        "username",
        "password",
        ce, 
        be
      )
    } yield xa

我正在使用以下代码查询 mysql

val table = "companies"
  val keyCol = "id"
  val columns = List("address",
                     "city",
                     "companyname",
                     "email",
                     "mobile",
                     "id",
                     "registerdate",
                     "registrationexp")


val queryString =
      s"""SELECT ${columns.mkString(", ")}
          FROM $table WHERE $keyCol = ? """
    log.debug(s"$queryString")
    transactor.use { xa =>
      {
        Query[Int, Company](queryString).option(id).transact(xa)
      }
    }

公司是具有上述列名的案例类

但低于错误

java.lang.ClassCastException: Cannot cast scala.Some to Company

我在哪里做错了

提前致谢

4

0 回答 0