Nasty little jdbc wrapper

gistfile1.scala

import java.sql._
import scala.util.Try

object DbEnv {

  trait Closeable {
    def close: Unit
  }

  def arm[T <: Closeable,X](r: => T)(f: T => X) = {
    val res = f(r)
    r.close
    res
  }

  type EnvF = () => Env

  private val dateFormat = new java.text.SimpleDateFormat("MM/dd/YYYY")

  implicit class ReadClob(clob: Clob) {
    def read = clob.getSubString(1, clob.length.toInt)
  }

  class QueryRecord(rs: ResultSet) {
    def mapOnFields(fields: Seq[String]): Map[String,String] = 
      Map[String,String](
      (for { 
        name <- fields
        value <- getAs[Object](name)
      } yield name -> value.toString):_*)

    def dateAsString(fieldName: String): String = 
      dateFormat.format(as(fieldName))

    def as[T](fieldName: String) = rs.getObject(fieldName).asInstanceOf[T]

    def getAs[T](fieldName: String) = Option(rs.getObject(fieldName)).flatMap(o => Try(o.asInstanceOf[T]).toOption)

    def getClob(name: String): Option[String] = getAs[Clob](name).map(_.read)

    def clob(name: String): String = as[Clob](name).read
    
  }

  class QueryResult(rs: ResultSet) {
    def map[T](func: QueryRecord => T): Seq[T] = {
      val lb = new scala.collection.mutable.ListBuffer[T]
      val qr = new QueryRecord(rs)
      while(rs.next) lb += func(qr)
      rs.close
      lb.toSeq
    }
    def foreach(func: QueryRecord => Unit) {
      val qr = new QueryRecord(rs)
      while(rs.next) func(qr)
      rs.close
    }
  }

  class Env(conn: Connection) extends Closeable {
    def query(qstr: String): QueryResult = new QueryResult(conn.prepareStatement(qstr).executeQuery)
    def idQuery(qStr: String, id: Int): QueryResult = {
      val stmt = conn.prepareStatement(qStr)
      stmt.setInt(1,id)
      new QueryResult(stmt.executeQuery)
    }

    def close { conn.close }
  }

}