Ordering system (java-based, database, jsp, servlet)

1 Home (login, registration)

(1) Display Time:

var time=new Date();
var year=time.getFullYear();
var month=time.getMonth();
var date=time.getDate();
var day=time.getDay();

(2) Log:

Submitted after the user submits the data via a form login, servlet get to the data of the data to the Dao layer, information of the user Dao layer query by a user name and password, if not the queried user information qualifying, then it proves that there is no user there is, if there is information about the user, is divided into two cases, namely: the user's identity for consumers or businesses, according to the above three cases, servlet will be based on the results returned were redirected to a different page.

(3) Registration:

First through the front of the form validation of user input to determine: is empty, the password meets the criteria, the two passwords are the same ...

After successful verification form can submit data to a form of the Servlet, Servlet invocation layer Dao, insertion operation, are displayed according to the corresponding information presentation will be successful after insertion returns the corresponding value, Servlet determines the return value.

2, shopping cart

(1) get all the product information:

After the need to add a shopping cart when the need to look at all the merchandise, pick your favorite product was added to the shopping cart, therefore, need to submit a request to the servlet through jsp, servlet heavy dao layer to obtain product information encapsulated in the request domain to forward the request the form of the commodity information display in the jsp page.

(2) view product details:

在展示商品全部信息的页面，点击相应的商品在页面获取该商品的ID并作为参数提交给Servlet，Servlet将该商品的ID作为Dao层的函数的参数，最终通过Dao层的sql语句，查询到对应商品的详细信息，请求转发到页面进行显示。

（3）添加购物车：

在商品的详细信息页面点击添加后，将对应商品的ID提交给了Servlet，Servlet会去查看session是否为空，如果为空，则需要通过Dao层获取到对应ID的商品的信息，将商品信息和商品在购物车中的数量（初始值为 0）封装在一个vo中，然后将该类的对象放到map集合，键为商品的ID，最后，将map集合放到session中。在购物车不为空的情况下，又分为两种情况：购物车里面已经有相同ID的商品数据了，此时，字需要将商品数量加1即可，另外一种情况是：购物车里面还没有相同ID的商品数据，则需要通过Dao层获取到对应ID的商品的信息，将商品信息和商品在购物车中的数量（初始值为 0）封装在一个vo中，然后将该类的对象放到map集合，键为商品的ID，最后，将map集合放到session中。

（4）查看购物车：

采用foreach语句来遍历session中的购物车中所有商品的信息和数量进行页面的显示，最后，还需要对所有商品遍历，求出购物车商品的总额并进行页面显示。

3、订单

（1）提交订单：