Question

我遇到了一个奇怪的问题，我的servlet doGet方法会运行三次。

我在Chrome和Firefox中对此进行了测试，结果相同。我还在另一台计算机上部署了该项目，并使用apache服务器查看该网站是否存在但是没有更改。

我在doGet中使用了一个开关，并在getParameter请求中找到了要运行的正确方法。我已将开关缩短为两种情况。但每次行动都是＆＃34;创造＆＃34;它将运行该方法三次。

我知道这是非常狭隘的，我希望我能够提供更多信息，但我不知道在哪里挖掘。

编辑：问题已经找到。 request.getRequestDispatcher正在导致它。非常感谢任何有关此问题的帮助。

protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {

        try {

        String action = request.getParameter("action");
        // To see that it runs 3 times.
        System.out.println(action);

        switch (action) {
        case "create":
           this.create(request, response);
           break;
        default:
           this.greetGuest(request, response);
           break;
    }
}

protected void createEvent(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {


        request.setAttribute("AbstractUser", SessionUser);
        // Here's the problem. This part will cause the doGet to be called multiply times.
        request.getRequestDispatcher("/WEB-INF/jsp/view/Organisation/create.jsp").forward(
                request, response);     
    }

protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {

        this.doGet(request, response);
    }


//html
<a href="eventHandler?action=create">Create</a>

//Configuration
@WebServlet(name = "eventHandler", urlPatterns = { "/eventHandler" }, loadOnStartup = 1)

//web.xml
   <jsp-config>
        <jsp-property-group>
            <url-pattern>*.jsp</url-pattern>
            <url-pattern>*.jspf</url-pattern>
            <page-encoding>UTF-8</page-encoding>
            <scripting-invalid>false</scripting-invalid>
            <include-prelude>/WEB-INF/jsp/base.jspf</include-prelude>
            <trim-directive-whitespaces>true</trim-directive-whitespaces>
            <default-content-type>text/html</default-content-type>
        </jsp-property-group>
    </jsp-config>

request.getRequestDispatcher（）以递归方式调用

0 个答案: