Java servlet 不分派(dispatch)到另一个 servlet

Question

我有 2 个 servlet，“HomeController”和“SearchController”。在 home.jsp 上，我有一个带有搜索框的表单，当向“搜索”提交操作时

 <form action="Search" method="post" name="searchForm">

所以 SearchController 做的第一件事是:

 @Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    if (!validator.isValidAlphaOnly(request.getParameter("breed"))) {
        request.setAttribute("error", "Breed search term invalid. Enter only letters");
        RequestDispatcher requestVar =  request.getRequestDispatcher("/Home");
        requestVar.forward(request, response);
    } else {
        processRequest(request, response);
    }
}

除了不会转到/Home，即使我有如下映射:

  <servlet>
    <servlet-name>HomeController</servlet-name>
    <servlet-class>Controllers.HomeController</servlet-class>
</servlet>
<servlet>
    <servlet-name>SearchController</servlet-name>
    <servlet-class>Controllers.SearchController</servlet-class>
</servlet>
<servlet>
    <servlet-name>DogController</servlet-name>
    <servlet-class>Controllers.DogController</servlet-class>
</servlet>
<servlet>
    <servlet-name>LogoutController</servlet-name>
    <servlet-class>Controllers.LogoutController</servlet-class>
</servlet>
<servlet>
    <servlet-name>UpdateController</servlet-name>
    <servlet-class>Controllers.UpdateController</servlet-class>
</servlet>
<servlet>
    <servlet-name>AddController</servlet-name>
    <servlet-class>Controllers.AddController</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>SearchController</servlet-name>
    <url-pattern>/Search</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>LogoutController</servlet-name>
    <url-pattern>/Logout</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>UpdateController</servlet-name>
    <url-pattern>/Update</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>AddController</servlet-name>
    <url-pattern>/Add</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>DogController</servlet-name>
    <url-pattern>/Dog/View/*</url-pattern>
    <url-pattern>/Dog/Edit/*</url-pattern>
    <url-pattern>/Dog/Add</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>HomeController</servlet-name>
    <url-pattern>/Home</url-pattern>
    <url-pattern>/</url-pattern>
</servlet-mapping>

Answer 1

您可以使用 getNamedDispatcher:

ServletContext context = getServletContext();
RequestDispatcher requestVar = context.getNamedDispatcher("HomeController");