Java EE：从POST获取参数以获取登录表单

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我试图实现一个简单的登录servlet，但它无法正常工作。

我想知道的是是如何通过使用HTTP POST的参数。它已经与HTTP GET一起使用，但用户名和密码可以从URL中看到。

< form method =postaction =home> < input name =usernameclass =form-logintitle =Usernamevalue =size =30maxlength =2048/> < input name =passwordtype =passwordclass =form-logintitle =Passwordvalue =size =30maxlength =2048/> < input type =submitvalue =连接> < / form>

web.xml

< servlet> < servlet-name>主页< / servlet-name> < servlet-class> controller.HomeController< / servlet-class> < / servlet> < servlet-mapping> < servlet-name>主页< / servlet-name> < url-pattern> / home< / url-pattern> < / servlet-mapping>

Servlet：

公共类HomeController扩展HttpServlet { 私有HttpSession会话; 私人UserBean userBean; public void doPost（HttpServletRequest请求，HttpServletResponse响应）抛出ServletException，IOException { UserBean user = new UserBean（）; String userName = request.getParameter（username）; String password = request.getParameter（password）; user.setUsername（userName）; user.setPassword（password）; user = UserDAO.login（user）; dispatch（request，response，ApplicationRessource.getInstance（）。getHomePage（））; protected void dispatch（HttpServletRequest请求， HttpServletResponse响应，String页面）抛出javax.servlet.ServletException，java.io.IOException { RequestDispatcher dispatcher = getServletContext（） .getRequestDispatcher（page）; dispatcher.forward（request，response）; $ / code $ / pre

问题在于 userName 和 password 字符串始终为空，这意味着永远不会从POST中获取参数。我做错了什么？

解决方案

它应该可以工作，您可以通过更改表单方法来获取并尝试检查，您应该看到参数在url中。

I am trying to implement a simple login servlet but it's not working properly.

What I wanted to know is how to pass the parameters using a HTTP POST. It already works with HTTP GET but the username and password are visible from the URL. It would be better to hide them in a POST.

<form method="post" action="home" > <input name="username" class="form-login" title="Username" value="" size="30" maxlength="2048" /> <input name="password" type="password" class="form-login" title="Password" value="" size="30" maxlength="2048" /> <input type="submit" value="Connect"> </form>

web.xml

<servlet> <servlet-name>home</servlet-name> <servlet-class>controller.HomeController</servlet-class> </servlet> <servlet-mapping> <servlet-name>home</servlet-name> <url-pattern>/home</url-pattern> </servlet-mapping>

Servlet:

public class HomeController extends HttpServlet { private HttpSession session; private UserBean userBean; public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { UserBean user = new UserBean(); String userName = request.getParameter("username"); String password = request.getParameter("password"); user.setUsername(userName); user.setPassword(password); user = UserDAO.login(user); dispatch(request, response, ApplicationRessource.getInstance().getHomePage()); } protected void dispatch(HttpServletRequest request, HttpServletResponse response, String page) throws javax.servlet.ServletException, java.io.IOException { RequestDispatcher dispatcher = getServletContext() .getRequestDispatcher(page); dispatcher.forward(request, response); } }

The problem is that the userName and password strings are always empty, meaning that the parameters are never fetched from the POST. What am I doing wrong?

解决方案

it should work, can you check by changing form method to get and trying, you should see parameters in url.