这是我的网络servlet。它的第一项工作是从数据库中检索国家/地区列表并在选择表单元素中打印出来。为此，一切正常。当我单击表单中的提交按钮时，我通过action="/submit"调用servlet。假设我在提交表单时没有插入任何用户名。 validateSignUpForm返回`true。而不是返回注册页面，我在提交页面。我不明白。当validationErrorFlag为true时，我应该回到注册页面而不是再次进入提交页面。错误在哪里？
@WebServlet(name = "SignUpServlet", urlPatterns =
{
"/signup"
})
public class SignUpServlet extends HttpServlet
{
@EJB
private UtilBeanInterface utilBean;
/**
* Handles the HTTP <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
request.setAttribute("CountriesList", utilBean.getContriesList());
request.getRequestDispatcher("/WEB-INF/view/signup.jsp").forward(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
String username = request.getParameter("username");
String password = request.getParameter("password");
String confirm_password = request.getParameter("confirm_password");
String email = request.getParameter("email");
String name = request.getParameter("name");
String surname = request.getParameter("surname");
String address = request.getParameter("address");
String city = request.getParameter("city");
String zipcode = request.getParameter("zip_code");
String country = request.getParameter("country");
String homenumber_code = request.getParameter("homenumber_code");
String homenumber = request.getParameter("homenumber");
String mobilenumber_code = request.getParameter("mobilenumber_code");
String mobilenumber = request.getParameter("mobilenumber");
boolean validationErrorFlag = false;
validationErrorFlag = utilBean.validateSignUpForm(username,
password,
confirm_password,
email,
name,
surname,
address,
city,
zipcode,
country,
homenumber_code,
homenumber,
mobilenumber_code,
mobilenumber,
request);
if(validationErrorFlag == true)
{
doGet(request, response);
}
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo()
{
return "Short description";
}
}
JSP PAGE
<article class="container_12">
<section id="signupform" class="grid_5">
<h4>Registrazione membri</h4>
<p>(*) Campi richiesti</p>
<h6>I tuoi dati d'accesso su VolaConNoi.it</h6>
<form action="submit" method="POST">
<div>
<label>Username* <span class="advice">(max 16 caratteri)</span></label>
<input type="text" name="username" autofocus>
<c:if test="${!empty usernameInvalid}">
<p class="errorSignUp">Errore: inserisci un username valido</p>
</c:if>
<c:if test="${!empty usernameAlreadyExist}">
<p class="errorSignUp">Errore: l'username è già in uso</p>
</c:if>
</div>
<div>
<label>Password*</label>
<input type="password" name="password">
</div>
<div>
<label>Conferma Password*</label>
<input type="password" name="confirm_password">
</div>
<div>
<label>E-mail*</label>
<input type="email" name="email">
</div>
<br/>
<h6>Dati Personali</h6>
<div>
<label>Nome*</label>
<input type="text" name="name">
</div>
<div>
<label>Cognome/i*</label>
<input type="text" name="surname">
</div>
<div>
<label>Indirizzo*</label>
<input type="text" name="address">
</div>
<div>
<label>Città*</label>
<input type="text" name="city">
</div>
<div>
<label>CAP*</label>
<input type="text" name="zip_code">
</div>
<div>
<label>Paese*</label>
<select name="country">
<c:forEach items="${CountriesList}" var="country">
<option value="${country.iso}">${country.nicename}</option>
</c:forEach>
</select>
</div>
<div>
<label>Fisso</label>
<select name="homenumber_code">
<c:forEach items="${CountriesList}" var="country">
<option value="${country.phonecode}">${country.nicename} (+${country.phonecode})</option>
</c:forEach>
<input type="text" name="homenumber">
</select>
</div>
<div>
<label>Mobile*</label>
<select name="mobilenumber_code">
<c:forEach items="${CountriesList}" var="country">
<option value="${country.phonecode}">${country.nicename} (+${country.phonecode})</option>
</c:forEach>
</select>
<input type="text" name="mobilenumber">
</div>
<div>
<input type="submit" value="Registrati"/>
</div>
</form>
<div id="signupfooter"></div>
</section>
</article>
答案 0 :(得分：1)
比较
@WebServlet(name = "MainControllerServlet",
loadOnStartup = 1,
urlPatterns = {"/signup",
"/submit"})
使用：
String url = "/WEB-INF/view" + userPath + ".jsp";
即使userPath = "/signup";你永远不会进入注册servlet，因为你提到了＃34; .jsp＆＃34;在那里。
另外，如果你曾经到过/signup，它看起来就像一个无限循环一遍又一遍地转发给自己。