The realization of the function of Java Web Development shopping Cart

In order to facilitate their review later, so write more carefully, record their growth.

Since it is a shopping cart, then the precondition is to first need a series of goods, that is, to build an entity, here a commodity table,

Display on a browser through a query

The basic display has been done, now into our plays, Servlet

When you click into the cart, the servlet will be accessed

Shopping Cart Code

1  PackageCom.servlet;2 3 Importjava.io.IOException;4 ImportJava.io.PrintWriter;5 ImportJava.util.HashMap;6 ImportJava.util.Map;7 8 Importjavax.servlet.ServletException;9 ImportJavax.servlet.http.HttpServlet;Ten Importjavax.servlet.http.HttpServletRequest; One ImportJavax.servlet.http.HttpServletResponse; A  - ImportCom.dao.GoodsDAO; - ImportCom.entity.Goods; the ImportCom.entity.GoodsItem; -  -  Public classPutcarservletextendsHttpServlet { -  +      Public voiddoget (httpservletrequest request, httpservletresponse response) -             throwsservletexception, IOException { +  AResponse.setcontenttype ("text/html"); atPrintWriter out =Response.getwriter (); -          - DoPost (request, response); -     } -  -      Public voidDoPost (httpservletrequest request, httpservletresponse response) in             throwsservletexception, IOException { -  toResponse.setcontenttype ("text/html"); +PrintWriter out =Response.getwriter (); -         //Get number theString id = request.getparameter ("Goodsid"); *          $         //get all information about a product object by numberPanax NotoginsengGoodsdao DAO =NewGoodsdao (); -Goods g =Dao.getgoodsbyid (ID); the         //put the item into the shopping cart +          A         //The Map collection is the shopping cart the         //map< Key, Value > Item number as key item as value +          -         //1. Determine if there is a shopping cart $         //The shopping cart is placed in the session. $         //pick up the shopping cart from the session -Map<string,goodsitem> GWC = (map<string,goodsitem>) request.getsession (). getattribute ("GWC"); -         //determine if there is the         if(gwc==NULL){ -             //Create a shopping cartWuyiGWC =NewHashmap<string, goodsitem>(); the         } -          Wu         //put items into your shopping cart -         //put (item number, item) add data to the GWC collection About         //You want to see if the item already exists in the shopping cart $         //in the GWC collection to match whether there is such a commodity item = = "Go to the collection to match whether there is such a product number of key -          -         //key to determine if a product number exists -      A         if(Gwc.containskey (id)) { +             //exist the             //Set Number +1 -              $             //get a value by key the             //The key is the item number value for the commodity item item contains the Product object information and the quantity information theGoodsitem SPX =gwc.get (ID); the             //get the original number the             intYLDSL =Spx.getcount (); -             //in the original number of +1 inGwc.get (ID). SetCount (yldsl+1); the              the //gwc.get (ID). SetCount (Gwc.get (ID). GetCount () +1); About              the}Else{ the             //does not exist the             //Create a new item quantity of 1 +Goodsitem GI =NewGoodsitem (g, 1); -              the             //put this item into the GWCBayi gwc.put (id, GI); the         } the          -         //put the cart into session -Request.getsession (). SetAttribute ("GWC", GWC); the          the         //Continue shopping theResponse.sendredirect ("index.jsp"); the     } -  the}

Execution Result:

The realization of the function of Java Web Development shopping Cart