jsp - 重定向后的 Liferay portlet doView()

Question

我有一个带有几个 jsp 页面的 portlet，每个页面都包含一个带有提交按钮的表单。当用户在第一个 jsp 上提交表单时，我将数据保存在 db 中并调用 actionResponse.sendRedirect() 将用户转发到下一个 jsp 页面。我必须使用重定向，以防止用户意外地按 F5 在下一页上重新提交相同的数据。一切工作正常，除了重定向到第二页后， doView() 方法未执行，并且我需要在渲染页面之前加载一些数据。这是正常行为还是我做错了什么？在渲染第二个 jsp 之前我可以在哪里加载该数据？

第一个jsp

<%-- ... --%>
<portlet:actionURL name="createNewMyCustomObj" var="createNewMyCustomObjURL" />
<aui:form action="<%= createNewMyCustomObjURL.toString() %> method="post">
    <%-- form fields --%>
    <aui:button type="submit" value="Create" />
</aui:form>

第二个jsp

<%
    MyCustomObj obj = (MyCustomObj) renderRequest.getAttribute("myCustomObj");
%>

<portlet:actionURL name="updateMyCustomObj" var="updateMyCustomObjURL" />
<aui:form action="<%= updateMyCustomObjURL.toString() %> method="post">
    <%-- fields with values from myCustomObj --%>
    <aui:button type="submit" value="Update" />
</aui:form>

MyMVCPortlet.java

public class MyMVCPortlet extends MVCPortlet {

    public createNewMyCustomObj(ActionRequest actionRequest,
         ActionResponse actionResponse) throws IOException, PortlalException, SystemException {

        PortletURL redirectURL = null;
        try {
            // get data from request
            // save it to db
            redirectURL = createRedirectURL(actionRequest, "second.jsp");
        } catch(Exception e) {
            SessionErrors.add(actionRequest, "error-key")
            // errors saving data, stay on the same page
            redirectURL = createRedirectURL(actionRequest, "first.jsp");
        }
        actionResponse.sendRedirect(redirectURL.toString());
    }

    private PortletURL createRedirectURL(ActionRequest actionRequest, String jspPage) {
        ThemeDisplay themeDisplay = (ThemeDisplay)         actionRequest.getAttribute(WebKeys.THEME_DISPLAY);
        String portletName = (String) actionRequest.getAttribute(WebKeys.PORTLET_ID);

        PortletURL redirectURL = PortletURLFactoryUtil.create(
            actionRequest, portletName, themeDisplay.getLayout().getPlid(),      PortletRequest.RENDER_PHASE);
        redirectURL.setParameter("jspPage", jspPage);

        return redirectURL;
    }

    @Override
    public void doView(RenderRequest renderRequest, RenderResponse renderResponse)
        throws IOException, PortletException {

        /*
         * doView() is never called after redirecting to second.jsp
         */
        if(/* second jsp page */) {
            // get myCustomObj created previously
            renderRequest.setAttribute("myCustomObj", myCustomObj);
        }
        super.doView(renderRequest, renderResponse);
    }
}

Answer 1

看一下 MVCPortlet 中的 MVCPortlet.doDispatch(RenderRequest renderRequest, RenderResponse renderResponse) 方法 - 在我看来，如果 mvcPath 或 jspPage 参数随请求一起发送，然后 doDispatch 方法完全忽略 doView 方法并直接路由到 JSP 页面。

如果您想在每个 portlet 渲染上运行 doView 方法，那么我建议忽略这些参数并在您的 doView 中自行进行路由。只需在 doView 末尾调用 include(path, renderRequest, renderResponse); 方法，其中 path 参数是您所需的 JSP 页面路径.

根据您编辑的问题，您可能想尝试如下操作:

MyMVCPortlet.java

public class MyMVCPortlet extends MVCPortlet {
    //...        

    private PortletURL createRedirectURL(ActionRequest actionRequest, String jspPage) {
        ThemeDisplay themeDisplay = (ThemeDisplay)         actionRequest.getAttribute(WebKeys.THEME_DISPLAY);
        String portletName = (String) actionRequest.getAttribute(WebKeys.PORTLET_ID);

        PortletURL redirectURL = PortletURLFactoryUtil.create(
            actionRequest, portletName, themeDisplay.getLayout().getPlid(),      PortletRequest.RENDER_PHASE);
        redirectURL.setParameter("viewName", jspPage); // note the changed parameter name

        return redirectURL;
    }

    @Override
    public void doView(RenderRequest renderRequest, RenderResponse renderResponse)
        throws IOException, PortletException {

        if(/* ... */) {
            // ...
        }
        String requestedView = renderRequest.getParameter("viewName");
        if (StringUtils.isBlank(requestedView)) { // StringUtils comes from commons-lang
            include(viewTemplate, renderRequest, renderResponse); // viewTemplate is a protected variable, which may also be called viewJSP depending on Liferay version I think
        } else {
            include(requestedView, renderRequest, renderResponse);
        }
    }
}