chrome/third_party/mock4js/examples/PriceService.js

   1 /**
   2  * PriceCache
   3  */
   4 function PriceCache() {
   5 }
   6
   7 PriceCache.prototype = {
   8         getCachedPrice: function(instrumentId) {
   9         },
  10         setCachedPrice: function(instrumentId, price) {
  11         }
  12 }
  13
  14 /**
  15  * PriceFetcher
  16  */
  17 function PriceFetcher() {
  18 }
  19
  20 PriceFetcher.prototype = {
  21         getPriceFromServer: function(instrumentId) {
  22         }
  23 }
  24
  25
  26 /**
  27  * PriceService
  28  */
  29 function PriceService(priceFetcher, priceCache) {
  30         this._priceFetcher = priceFetcher;
  31         this._priceCache = priceCache;
  32 }
  33
  34 PriceService.prototype = {
  35         getPrice: function(instrumentId) {
  36                 var price = this._priceCache.getCachedPrice(instrumentId);
  37                 if(price==null) {
  38                         price = this._priceFetcher.getPriceFromServer(instrumentId);
  39                         this._priceCache.setCachedPrice(instrumentId, price);
  40                 }
  41                 return price;
  42         }
  43 }