processFile

 if let jsonDictionary = jsonDict {
      println("json parsed successfully")
      let total = jsonDictionary["centres"]!.count
      let json_data = JSONValue(jsonDictionary)
      if json_data{
          for var index = 0; index < total; ++index {
              var name = json_data["centres"][index]["name"].string
              if name {
                //processing value
              }
          }
      }
  }