gistfile1.txt

def all[T : RootJsonFormat](esDocConf: ESDocConf, batchSize: Int = 100): Iterator[T] = 
  new Iterator[T] {
    var i = 0
    private def read() = {
      val items = read(esDocConf, i * batchSize, batchSize)
      i = i + 1
      items
    }
    private var batch = read()

    override def hasNext: Boolean = {
      if (batch.isEmpty) {
        batch = read
      }
      
      !batch.isEmpty
    }
    
    override def next: T = {
      if (batch.isEmpty) {
        batch = read
      }

      val top = batch.head
      batch = batch.tail
      top
    }
  }