这是我正在编写的一个简单程序，用于理解 @RequestMapping 注释等。我有两个控制器。home 控制器是主页并呈现 home.jsp。团队控制器处理 team.jsp。主页上有一个删除团队表单，用于从数据库中删除团队对象。这工作得很好。要添加团队，用户单击将他们带到 team.jsp 的链接。在该页面上，用户可以输入新团队的数据。一旦用户输入此信息，数据库就会成功更新。函数“storeTeam”然后返回到家庭控制器中的“家”。这就是问题发生的地方：我收到此消息：
“ Bean 名称 'removedTeam' 的 BindingResult 和普通目标对象都不能用作请求属性”
当应该调用 home 函数以使用数据库内容重新填充表时，为什么在 home 控制器中调用“removeAteam”函数？以下是相关文件。谢谢您的帮助。
HomeController.java
package com.ryans.MVCproject1;
import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
/**
* Handles requests for the application home page.
*/
@Controller
@RequestMapping(value="/")
public class HomeController {
private static final Logger logger = LoggerFactory.getLogger(HomeController.class);
@Autowired
Greeter umpire;
@Autowired
Team removedTeam;
@Autowired baseballService baseballservice; //all teams in the database
/**
* Simply selects the home view to render by returning its name.
*/
@RequestMapping(value = {"/","home"}, method = RequestMethod.GET)
public String home(Locale locale, Model model) {
logger.info("Welcome home! the client locale is "+ locale.toString());
Date date = new Date();
DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG, locale);
String formattedDate = dateFormat.format(date);
Greeter friend = new Greeter();
model.addAttribute("serverTime", formattedDate );
model.addAttribute("friend",friend);
model.addAttribute("umpire",umpire);
model.addAttribute("removedTeam",removedTeam);
getAllTeams(model);
return "home";
}
public void getAllTeams(Model model){
logger.info("Getting all teams...");
List<Team> allTeams = baseballservice.getAllTeams(); //Query for all teams in database
//mav.addObject("GET_TEAMS_KEY", allTeams);
model.addAttribute("allTeams", allTeams);
return;
}
@RequestMapping("removeAteam")
public String removeAteam(@ModelAttribute("removedTeam")Team theRemovedTeam, BindingResult result,Model model){
logger.info("Removing team...");
baseballservice.removeTeam(theRemovedTeam.getTeamName()); //the teamName is being pulled from the model as entered in the jsp form
getAllTeams(model);
return "home";
}
}
TeamController.java
package com.ryans.MVCproject1;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
/**
*
* @author Ryan
*
* Handle Requests for the team page
*
*/
@Controller
@RequestMapping(value="/team")
public class TeamController {
private static final Logger logger = LoggerFactory.getLogger(TeamController.class);
@Autowired
private Team theTeam;
@Autowired
private baseballService teamManager;
@RequestMapping(method=RequestMethod.GET)
public String TeamPage(Model model){
logger.info("You have entered the team controller.");
model.addAttribute("theTeam", theTeam);
return "team";
}
@RequestMapping("/storeTeam")
public String storeTeam(@ModelAttribute("theTeam")Team enteredTeam,BindingResult result){
teamManager.saveTeam(enteredTeam); //the @ModelAttribute is binding to the model attribute added in the get method
return "home";
}
}
这些是控制器，这里是视图：
主页.jsp
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://www.springframework.org/tags" prefix="s"%>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
<%@ page session="false"%>
<html>
<head>
<title>Basic Baseball Player and Team Manager</title>
</head>
<body>
<h1>Current Teams in the MLB Database</h1>
<h1>Current Players in the League</h1>
<p> ${friend.theMessage} ${umpire.theMessage}</p>
<a href="team">Create New Team</a>
<table style="border-collapse: collapse;" width="500" border="1"
bordercolor="#006699">
<tbody>
<tr bgcolor="lightblue">
<th>Id</th>
<th>Team Name</th>
<th>City</th>
<th>No. of Players</th>
<th></th>
</tr>
<c:forEach var="team" items="${allTeams}">
<tr>
<td colspan="4"></td>
</tr>
<tr>
<td><c:out value="${team.id}"></c:out></td>
<td><c:out value="${team.teamName}"></c:out></td>
<td><c:out value="${team.city}"></c:out></td>
<td></td>
<td></td>
</tr>
</c:forEach>
</tbody>
</table>
<form:form method="POST" modelAttribute="removedTeam" action="removeAteam">
<td>Team Name</td><form:input path="teamName"/>
<td><input type="submit" value="remove team"/> </td>
</form:form>
</body>
</html>
团队.jsp
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://www.springframework.org/tags" prefix="s" %>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Team Maker</title>
</head>
<body>
<h3>Welcome to the Team Generator</h3>
<form:form method="POST" modelAttribute="theTeam" action="team/storeTeam">
<table>
<tr>
<td>Team Name:</td>
<td><form:input path="teamName" /></td>
</tr>
<tr>
<td>City:</td>
<td><form:input path="city" /></td>
</tr>
<tr>
<td colspan="2">
<input type="submit" value="Create Team" />
</td>
</tr>
</table>
</form:form>
<a href="home">Back Home</a>
</body>
</html>
这是 servlet 上下文：
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<!-- DispatcherServlet Context: defines this servlet's request-processing
infrastructure -->
<!-- Enables the Spring MVC @Controller programming model -->
<annotation-driven />
<!-- Enables the transactional annotations -->
<tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven>
<!-- Handles HTTP GET requests for /resources/** by efficiently serving
up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />
<!-- Connection to Database
***** hsqldb.lock_file=false *****
-->
<beans:bean id="datasource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<beans:property name="driverClassName" value="org.hsqldb.jdbcDriver" />
<beans:property name="url" value="jdbc:hsqldb:G:/SpringProjects/MVCProj1/database;shutdown=true" />
<beans:property name="username" value="ryan" />
<beans:property name="password" value="ryan" />
</beans:bean>
<!-- Resolves views selected for rendering by @Controllers to .jsp resources
in the /WEB-INF/views directory -->
<!-- View Resolver -->
<beans:bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean>
<!-- MessageSource -->
<beans:bean
class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<beans:property name="basename" value="classpath:messages" />
<beans:property name="defaultEncoding" value="UTF-8" />
</beans:bean>
<!-- Hibernate SessionFactory -->
<beans:bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<!-- <beans:bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> -->
<beans:property name="dataSource" ref="datasource"></beans:property>
<beans:property name="configLocation" value="classpath:hibernate.cfg.xml"></beans:property>
<beans:property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration"></beans:property>
<!-- <beans:property name="annotatedClasses">
<beans:list>
<beans:value>com.ryans.MVCproject1.Team</beans:value>
</beans:list>
</beans:property> -->
<beans:property name="hibernateProperties">
<beans:props>
<beans:prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</beans:prop>
<beans:prop key="hibernate.show_sql">true</beans:prop>
<beans:prop key="hibernate.hbm2dll.auto">create</beans:prop>
</beans:props>
</beans:property>
</beans:bean>
<!-- Define a transaction Manager -->
<beans:bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<beans:property name="sessionFactory" ref="sessionFactory"></beans:property>
</beans:bean>
<!-- Custom Greeter Bean -->
<beans:bean id="umpire" class="com.ryans.MVCproject1.Greeter">
<beans:property name="theMessage" value="I am the umpire!"></beans:property>
</beans:bean>
<beans:bean id="theTeam" class="com.ryans.MVCproject1.Team"></beans:bean>
<beans:bean id="removedTeam" class="com.ryans.MVCproject1.Team"></beans:bean>
<beans:bean id="baseballDAO" class="com.ryans.MVCproject1.BaseballDAOimp">
<beans:property name="sessionFactory" ref="sessionFactory"></beans:property>
</beans:bean>
<beans:bean id="baseballservice" class="com.ryans.MVCproject1.baseballServiceImp">
<beans:constructor-arg ref="baseballDAO"></beans:constructor-arg>
</beans:bean>
<beans:bean id="teamManager" class="com.ryans.MVCproject1.baseballServiceImp">
<beans:constructor-arg ref="baseballDAO"></beans:constructor-arg>
</beans:bean>
<context:component-scan base-package="com.ryans.MVCproject1" />
</beans:beans>
...最后是 web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/root-context.xml</param-value>
</context-param>
<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Processes application requests -->
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>appServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>