java - SprinMVC 控制流程

Question

我想在 Spring MVC 中重写 servlet 控制流，这是我的Servlet 中的 doGet

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String action = request.getParameter("action");

        String path = request.getParameter("path");

        if (path != null && path.equals("register")) {
            RequestDispatcher view = request.getRequestDispatcher("/WEB-INF/views/system/registeruser.jsp");
            view.forward(request, response);
        } else if (path != null && path.equals("usermang")) {
            RequestDispatcher view = request.getRequestDispatcher("/WEB-INF/views/system/manageuser.jsp");
            view.forward(request, response);
        }

    else {
            PrintWriter out = response.getWriter();
            out.print("Served at: " + request.getContextPath());
            RequestDispatcher view = request.getRequestDispatcher("/WEB-INF/views/system/index.jsp");
            view.forward(request, response);
        }
    }

我想使用模型和 View 将上面的 doGET 转换为 Spring RequestMapping示例

@RequestMapping(value ="/grcon" ,method = RequestMethod.GET)
    public ModelAndView getGrcon()

        ModelAndView modegeron = new ModelAndView("index");

if (path != null && path.equals("register")) {
      view = request.getRequestDispatcher("/WEB-INF/views/system/registeruser.jsp");

        return modegeron;

    }
}

Answer 1

你正在变得复杂，使用 Spring 的力量来为你处理复杂性。

对于初学者来说，将 InternalResourceViewResolver 添加到您的配置中，这将处理 View 到资源的转换。

<bean id="viewResolver" class="InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/views/system/" />
    <property name="suffix" value=".jsp" />
</bean>

接下来添加params元素到您的@RequestMapping以获得映射的进一步规范。

@RequestMapping(value ="/grcon", method = RequestMethod.GET, params="path=register")
public String register() {
    return "registeruser";
}

@RequestMapping(value ="/grcon", method = RequestMethod.GET, params="path= usermang")
public String manageUser() {
    return "manageuser";
}

@RequestMapping(value ="/grcon", method = RequestMethod.GET)
public String index() {
    return "index";
}

或者使用具有@RequestParam的方法并返回适当的 View 。进行 String 比较时的小提示将静态值放在第一位，这样可以节省 null 检查。

@RequestMapping(value ="/grcon", method = RequestMethod.GET)
public String register(@RequestParam(value="path", required=false) String path) {
    if ("register".equals(path) ) {
        return "registeruser";
    } else if ("usermang".equals(path)) {
        return "manageuser";
    }
    return "index";
}

但是，通常您还需要对模型做一些准备，因此第一个可能更适用。