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java - Spring MVC 中模型对象未传递给 jsps - InternalResourceView - renderMergedOutputModel

转载 作者:行者123 更新时间:2023-11-30 04:22:01 25 4
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我在我的项目中使用 JSTLView Spring Tiles。

当我尝试通过 Controller 将 form:errors 从 validator 发送到 jsp 时,jsp 中不会显示错误

当我调试时,

1)在从 validator 类返回 modelandview 之前,在 Controller 类中打印错误。

2)然后错误也在 Controller 类的 JSTLView 类中打印。

所以我认为,jSTLview类中的requestDispatcher.forward(request, response)并没有将模型数据返回到jsp。

因为当我尝试 HttpServletRequest 或 HttpServletResponse 对象来检索 jsp 中的错误时,值在 jsp 中显示。

有人可以帮我解决这个问题吗?

如何将模型数据发送到 jsp renderMergedOutputModel- RequestDispatcher ,重定向方法。

我的代码如下,

JSTLView类:

public class JstlView extends InternalResourceView {

@Override
protected void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception {

// Determine the path for the request dispatcher.
String dispatcherPath = prepareForRendering(request, response);

// set original view being asked for as a request parameter
request.setAttribute("partial", dispatcherPath.substring(dispatcherPath.lastIndexOf("/") + 1));

// force everything to be template.jsp
RequestDispatcher requestDispatcher = request.getRequestDispatcher("/WEB-INF/jsp/template.jsp");
requestDispatcher.forward(request, response);

System.out.println("**********************"+model.get("userName"));
}

}

Servlet.xml

<bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">

<property name="viewClass" value="com.tms.web.view.JstlView" />

<property name="prefix" value="/WEB-INF/jsp/" />

<property name="suffix" value=".jsp" />
</bean>

Controller :

 private LoginValidator loginValidator;
@Autowired
public void setUserValidator(LoginValidator loginValidator) {
this.loginValidator = loginValidator;
}

final RequestHandler requestHandler = new RequestHandler();
@RequestMapping(value = "/login", method = RequestMethod.GET)
public ModelAndView login() {
return new ModelAndView("login", "users", new users());
}

@RequestMapping(value = "/logins",method = RequestMethod.POST)
public ModelAndView validateUser(@Valid users user, BindingResult result,@ModelAttribute("users")users users,ModelMap model,RedirectAttributes redirectAttributes,HttpServletRequest req)
{
this.loginValidator.validate(user, result);
if (result.hasErrors())
{
model.putAll(result.getModel());//values not retuned to jsp
req.setAttribute("userName", result.getFieldError().getDefaultMessage().toString()); //working fine values retuned to jsp
return new ModelAndView("/login", model);
}
else
{
//succes related code
return new ModelAndView(redirect, model);
}
}

validator

@Component
public class LoginValidator implements Validator {

@Override
public boolean supports(Class<?> clazz) {

return clazz.isAssignableFrom(users.class);
}
@Override
public void validate(Object obj, Errors errors) {
users user = (users) obj;
String userName = user.getUserName();
String password = user.getPassword();
validateuserName(userName,password, errors);
}

private void validateuserName(String userName, String password,Errors errors) {
if (!(isValidString(userName))) {
errors.rejectValue("userName", "userName.required","Username should not be blank");
}
else if(!(isValidString(password)))
{
errors.rejectValue("password", "password.required","Password should not be blank");
}
}

private boolean isValidString(String str) {
return isNotNull(str) && (str.length() > 0 ) && !(str.isEmpty());
}

private boolean isNotNull(String str) {
return str != null;
}
}

Jsp

<%@ page language="java" contentType="text/html;charset=UTF-8; charset=ISO-8859-1"
pageEncoding="ISO-8859-1" %>
<%@ page isScriptingEnabled="true" isELIgnored="false" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@taglib uri="http://www.springframework.org/tags" prefix="spring"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>



<form:form method="POST" action="/TMSWeb/logins" commandName="users" modelAttribute="users">
<input name="password" type="password" align="center"/>
<form:errors path="password" cssClass="error" element="div" />
<input type="submit" class="buttonorange" value="Login"/>
</form:form>

在 Spring MVC 中,当我可以在没有 JSTLView 的情况下访问 JSP 中的 bean 时,那么,在我的 JSP 中我可以编写 (${errors)。但是,当同一个 JSP 是图 block View 的一部分时,这些属性就无法访问。

有人可以帮我解决这个问题吗?

最佳答案

您正在 JSTLView 类中扩展类 org.springframework.web.servlet.view.InternalResourceView 并覆盖 renderMergedOutputModel 方法,其中您缺少公开模型对象。从重写方法中调用此方法 exposeModelAsRequestAttributes(model, requestToExpose); ,如下所示。尝试使用下面的代码,这对我有用。

@Override
protected void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception {

// Expose the model object as request attributes.
exposeModelAsRequestAttributes(model,request);

// Determine the path for the request dispatcher.
String dispatcherPath = prepareForRendering(request, response);

// set original view being asked for as a request parameter
request.setAttribute("partial", dispatcherPath.substring(dispatcherPath.lastIndexOf("/") + 1));

// force everything to be template.jsp
RequestDispatcher requestDispatcher = request.getRequestDispatcher("/WEB-INF/jsp/template.jsp");
requestDispatcher.forward(request, response);

System.out.println("**********************"+model.get("userName"));
}

}

关于java - Spring MVC 中模型对象未传递给 jsps - InternalResourceView - renderMergedOutputModel,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16835364/

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