Make Array of Objects from json_encode

I have this object

stdClass Object (
  [reportDate] => 2014-02-02
  [shops] => Array (
    [24] => stdClass Object (
      [shopid] => 24
      [cashiers] => Array (
        [1] => stdClass Object (
          [cashierid] => 1
          [products] => Array (
            [moneyIn] => 46
            [moneyOut] => 215.14
          )
        )
      )
    )
  )
) 

And When i make json_encode on it I get this json string

   {
      "reportDate":"2014-02-02",
      "shops":{
        "24":{
          "shopid":24,
          "cashiers":{
            "1":{
              "cashierid":1,
              "products":{
                "moneyIn":"46",
                "moneyOut":"215.14"
              }
            }
          }
        }
      }
    }

This result is not what I wanted. I want array of objects.

So instead of this "shops":{ I want this "shops":[ Instead of this "cashiers":{ I want this "cashiers":[ And so on.

Where ever there is an array in my stdClass I want array and where there is stdClass I want object.

So what am I doing wrong in structuring my initial stdClass Object.