Java 加载后而非提交后的控制器加载错误消息
尝试找出当我加载jsp页面时，即使我没有提交按钮，也会显示错误消息。任何人都可以建议如何在提交按钮后显示错误消息。我把我的代码贴在这里进行控制。 提前谢谢 登录控制器Java 加载后而非提交后的控制器加载错误消息,java,spring,model-view-controller,web-applications,Java,Spring,Model View Controller,Web Applications,尝试找出当我加载jsp页面时，即使我没有提交按钮，也会显示错误消息。任何人都可以建议如何在提交按钮后显示错误消息。我把我的代码贴在这里进行控制。 提前谢谢 登录控制器 @Controller //@RequestMapping("/") public class LoginController { @Autowired private LoginService loginServiceImpl; @RequestMapping(value="/login", met
@Controller
//@RequestMapping("/")
public class LoginController {
@Autowired
private LoginService loginServiceImpl;
@RequestMapping(value="/login", method = { RequestMethod.GET, RequestMethod.POST })
public ModelAndView validUser(@ModelAttribute("person") PersonModel personModel) {
ModelAndView model= new ModelAndView("login");
try
{
boolean validUser = loginServiceImpl.isValidUser(personModel.getName(), personModel.getPassword());
//Zjistí zda-li je user přihlášen
if(validUser)
{
System.out.println("User Login Successful");
model.addObject("successMessage", personModel.getName());
}
else
{
System.out.println("Login wasn't Successful");
model.addObject("unsuccessmessage", "Invalid credentials!!");
}
}
catch(Exception e)
{
e.printStackTrace();
}
return model;
}
}
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<html>
<head>
<title>Login Page</title>
</head>
<body>
<form:form id="loginForm" method="post" action="login" modelAttribute="person">
<form:label path="name">Login name:</form:label>
<form:input id="name" name="name" path="name" /><br>
<form:label path="password">Password</form:label>
<form:password id="password" name="password" path="password" /><br>
<input type="submit" value="Submit" />
<h2>${unsuccessMessage}</h2>
<h2>${successMessage}</h2>
</form:form>
</body>
</html>
登录页面
登录名：
密码
${unsuccessMessage}
${successMessage}