如何在JSP中显示对象的数据 [英] How to display data of objects in JSP
本文介绍了如何在JSP中显示对象的数据的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我通过寄存器形式将一些用户详细信息存储到db（hibernate和spring）中。我想在单独的JSP页面中显示所有用户的用户详细信息。请有人告诉我该怎么做？
以下是我的控制器代码
@Controller
public class RegisterController {
@Autowired
private UserDao userDao;
@RequestMapping（value =/registerForm.htm，method = RequestMethod.GET）
public ModelAndView registerPage（ModelMap map）{
User user = new User（）;
map.addAttribute（user）;
返回新的ModelAndView（registerForm，command，user）;
$ b @RequestMapping（value =/registerProcess.htm，method = RequestMethod.POST）
public ModelAndView registerUser（@ModelAttribute（user）用户用户，模型模型）{
model.addAttribute（userName，user.getUserName（））;
model.addAttribute（password，user.getPassword（））;
model.addAttribute（emailId，user.getEmailId（））;
System.out.println（user is+ user）;
System.out.println（userdao is+ userDao）;
userDao.saveUser（user）;
返回新的ModelAndView（registerProcess，user，user）;
}
}
userdao
public void saveUser（User user）{
Session session = getSessionFactory（）。openSession（） ;
交易tx;
tx = session.beginTransaction（）;
session.persist（user）;
tx.commit（）;
解决方案
在GET请求中获取要显示给用户的元素。这涉及以下步骤：
- 具有适当的URL映射和视图来处理GET。
- 获取将预处理您的URL的方法中的数据。
- 存储数据以作为请求属性显示给用户。
- 转发到查看（JSP）。
- 在视图中显示来自请求属性的数据。
A非常简单的例子基于你当前的代码，并假设存在一些方法：
@Controller
public class RegisterController {
@Autowired
private UserDao userDao;
@RequestMapping（value =/ registerForm.htm，method = RequestMethod.GET）
public ModelAndView registerPage（ModelMap map）{
User user = new User（）;
map.addAttribute（user）;
返回新的ModelAndView（registerForm，command，user）;
}
@RequestMapping（value =/ registerProcess.htm，method = RequestMethod.POST）
public ModelAndView registerUser（@ModelAttribute（user）User user，Model模型）{
model.addAttribute（userName，user.getUserName（））;
model.addAttribute（password，user.getPassword（））;
model.addAttribute（emailId，user.getEmailId（））;
System.out.println（user is+ user）;
System.out.println（userdao is+ userDao）;
userDao.saveUser（user）;
返回新的ModelAndView（registerProcess，user，user）;
}
//这是具有适当映射的新方法
@RequestMapping（value =/ userList.htm，method = RequestMethod.GET）
public ModelAndView registerPage（ModelMap map）{
//此方法应检索所有用户的数据
List< User> userList = userDao.getAllUsers（）;
map.addAttribute（userList，userList）;
返回新的ModelAndView（userList，map）;
然后，在userList.jsp中：
<％@ taglib prefix =curi =http://java.sun.com/ jsp / jstl / core％>
<！DOCTYPE html>
< html lang =en>
< head>
< title>使用者名单< / title>
< / head>
< body>
用户名单：
< br />
< table>
< c：forEach items =$ {userList}var =user>
< tr>
< td> $ {user.userName}< / user>
< / tr>
< / c：forEach>
< / table>
< / body>
< / html>
请注意，这是关于如何执行此操作的一个非常基本的示例。
更多信息：I have stored some user details through a register form into db (hibernate and spring). I want to display the user details of all users in a separate JSP page.Could anyone please tell me how to do that?
Below is my code of controller
@Controller
public class RegisterController {
@Autowired
private UserDao userDao;
@RequestMapping(value = "/registerForm.htm", method = RequestMethod.GET)
public ModelAndView registerPage(ModelMap map) {
User user = new User();
map.addAttribute(user);
return new ModelAndView("registerForm", "command", user);
}
@RequestMapping(value = "/registerProcess.htm", method = RequestMethod.POST)
public ModelAndView registerUser(@ModelAttribute("user") User user, Model model) {
model.addAttribute("userName", user.getUserName());
model.addAttribute("password", user.getPassword());
model.addAttribute("emailId", user.getEmailId());
System.out.println("user is " + user);
System.out.println("userdao is" + userDao);
userDao.saveUser(user);
return new ModelAndView("registerProcess", "user", user);
}
}
code inside userdao
public void saveUser(User user) {
Session session=getSessionFactory().openSession();
Transaction tx;
tx=session.beginTransaction();
session.persist(user);
tx.commit();
}
解决方案
You should obtain the elements you want to show to user in a GET request. This involves the following steps:
- Have a proper URL mapping and view to process the GET.
- Obtain the data in the method that will pre process your URL.
- Store the data to display to users as request attribute.
- Forward to the view (JSP).
- In view, display the data from request attributes.
A very simple example based on your current code and assuming the existence of some methods:
@Controller
public class RegisterController {
@Autowired
private UserDao userDao;
@RequestMapping(value="/registerForm.htm",method=RequestMethod.GET)
public ModelAndView registerPage(ModelMap map){
User user=new User();
map.addAttribute(user);
return new ModelAndView("registerForm","command",user);
}
@RequestMapping(value="/registerProcess.htm",method=RequestMethod.POST)
public ModelAndView registerUser(@ModelAttribute("user") User user,Model model){
model.addAttribute("userName", user.getUserName());
model.addAttribute("password", user.getPassword());
model.addAttribute("emailId",user.getEmailId());
System.out.println("user is "+user);
System.out.println("userdao is"+userDao);
userDao.saveUser(user);
return new ModelAndView("registerProcess","user",user);
}
//this is the new method with proper mapping
@RequestMapping(value="/userList.htm", method=RequestMethod.GET)
public ModelAndView registerPage(ModelMap map) {
//this method should retrieve the data for all users
List<User> userList = userDao.getAllUsers();
map.addAttribute("userList", userList);
return new ModelAndView("userList", map);
}
}
Then, in userList.jsp:
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html lang="en">
<head>
<title>User List</title>
</head>
<body>
List of users:
<br />
<table>
<c:forEach items="${userList}" var="user">
<tr>
<td>${user.userName}</user>
</tr>
</c:forEach>
</table>
</body>
</html>
Note that this is a very basic example about how to do this. The code can be heavily improved.
More info:
- How to pass parameter to jsp:include via c:set? What are the scopes of the variables in JSP?
- How to avoid Java code in JSP files?
这篇关于如何在JSP中显示对象的数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
