我在玩ScalikeJdbc图书馆。我想从PostgreSQL数据库中检索数据。我得到的错误对我来说很奇怪。即使我手动配置CP：

val poolSettings = new ConnectionPoolSettings(initialSize = 100, maxSize = 100)
ConnectionPool.singleton("jdbc:postgresql://localhost:5432/test", "user", "pass", poolSettings)

我仍然看到错误。这是我的DAO：

class CustomerDAO {

  case class Customer(id: Long, firstname: String, lastname: String)
  object Customer extends SQLSyntaxSupport[Customer]

  val c = Customer.syntax("c")

  def findById(id: Long)(implicit session: DBSession = Customer.autoSession) =
    withSQL {
      select.from(Customer as c)
    }.map(
      rs => Customer(
        rs.int("id"),
        rs.string("firstname"),
        rs.string("lastname")
      )
    ).single.apply()

}

该应用程序：

object JdbcTest extends App {
  val dao = new CustomerDAO
  val res: Option[dao.Customer] = dao.findById(2)
}

我的application.conf档案

# PostgreSQL
db.default.driver = "org.postgresql.Driver"
db.default.url = "jdbc:postgresql://localhost:5432/test"
db.default.user = "user"
db.default.password = "pass"

# Connection Pool settings
db.default.poolInitialSize = 5
db.default.poolMaxSize = 7
db.default.poolConnectionTimeoutMillis = 1000

错误：

Exception in thread "main" java.lang.IllegalStateException: Connection pool is not yet initialized.(name:'default)
    at scalikejdbc.ConnectionPool$$anonfun$get$1.apply(ConnectionPool.scala:57)
    at scalikejdbc.ConnectionPool$$anonfun$get$1.apply(ConnectionPool.scala:55)
    at scala.Option.getOrElse(Option.scala:120)
    at scalikejdbc.ConnectionPool$.get(ConnectionPool.scala:55)
    at scalikejdbc.ConnectionPool$.apply(ConnectionPool.scala:46)
    at scalikejdbc.NamedDB.connectionPool(NamedDB.scala:20)
    at scalikejdbc.NamedDB.db$lzycompute(NamedDB.scala:32)

我错过了什么？