Question

我正在尝试添加一个通用的Slick Entity / Table帮助程序类：

trait HasSlickProfile {
  val profile: JdbcProfile
}

trait SlickedDBConfig
  extends HasSlickProfile {
  lazy val profile: JdbcProfile = ???
}

abstract class EntityHelper[E]
  extends HasSlickProfile {

  import profile.api._

  type T <: Table[E]
  def table: TableQuery[_ <: Table[E]]

  // TONS OF USEFULL ENTITY / TABLE STUFF
}

但它不能编译：

object ValueOfHelper
  extends EntityHelper[ValueOf]
    with SlickedDBConfig {

  import profile.api._

  type T = ValueOfTable
  val table = ValueOfTable
}

因为发现了错误：

[error] /.../ValueOfHelper.scala:22: overriding type T in class EntityHelper with bounds <: fp.model.ValueOfHelper.profile.api.Table[fp.model.Tables.ValueOf];
[error]  type T has incompatible type
[error]   type T = ValueOfTable
[error]        ^
[error] /.../ValueOfHelper.scala:23: overriding method table in class EntityHelper of type => fp.model.ValueOfHelper.profile.api.TableQuery[_ <: fp.model.ValueOfHelper.profile.api.Table[fp.model.Tables.ValueOf]];
[error]  value table has incompatible type
[error]   val table = ValueOfTable
[error]       ^

自动生成的表格如下所示：

import slicked.codegen.SlickedDBConfig

object Tables extends {
} with Tables
  with SlickedDBConfig

trait Tables {
  val profile: slick.jdbc.JdbcProfile
  import profile.api._

  // Custom imports start
  import slicked.SlickedRow
  import slicked.SlickedTable
  import slicked.SlickMappers._
  // Custom imports end

  import slick.model.ForeignKeyAction
  import slick.jdbc.{GetResult => GR}

  lazy val schema: profile.SchemaDescription = ValueOfTable.schema

  case class ValueOf(of: String, in: String, timestamp: org.joda.time.DateTime, `val`: Int, info: Option[String] = None) extends SlickedRow

  implicit def GetResultValueOf(implicit e0: GR[String], e1: GR[org.joda.time.DateTime], e2: GR[Int], e3: GR[Option[String]]): GR[ValueOf] = GR{
    prs => import prs._
      ValueOf.tupled((<<[String], <<[String], <<[org.joda.time.DateTime], <<[Int], <<?[String]))
  }

  class ValueOfTable(_tableTag: Tag) extends profile.api.Table[ValueOf](_tableTag, Some("forex"), "VALUE_OF") with SlickedTable {
    def * = (of, in, timestamp, `val`, info) <> (ValueOf.tupled, ValueOf.unapply)
    def ? = (Rep.Some(of), Rep.Some(in), Rep.Some(timestamp), Rep.Some(`val`), info).shaped.<>({r=>import r._; _1.map(_=> ValueOf.tupled((_1.get, _2.get, _3.get, _4.get, _5)))}, (_:Any) =>  throw new Exception("Inserting into ? projection not supported."))
    val of: Rep[String] = column[String]("OF", O.Length(16,varying=true))
    val in: Rep[String] = column[String]("IN", O.Length(16,varying=true))
    val timestamp: Rep[org.joda.time.DateTime] = column[org.joda.time.DateTime]("TIMESTAMP")
    val `val`: Rep[Int] = column[Int]("VAL")
    val info: Rep[Option[String]] = column[Option[String]]("INFO", O.Default(None))
    val index1 = index("VALUEOF_TIMESTAMP_OF_IN_pk", (timestamp, of, in), unique=true)
  }

  lazy val ValueOfTable = new TableQuery(tag => new ValueOfTable(tag))
}

如何将其编写为与配置文件无关？

通用光滑实体/表助手

0 个答案: