Scala try-with-resources

  def using[A, B <: {def close() : Unit}](closeable: B)(f: B => A): A =
    try {
      f(closeable)
    } finally {
      closeable.close()
    }

用法

    using(getConnection(Config.properties())) {
      conn => deleteRecords(conn, srcTable, filterCondition)
    }

扩展

def using2[A, B <: {def close(): Unit}, C <: { def close(): Unit}](closeB: B, closeC: C)(f: (B,C) => A): A = {
  try { f(closeB,closeC) } finally { closeB.close(); closeC.close() }
}