Spring <form:select> 标签在 Spring mvc + Hibernate 应用程序中导致错误
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【中文标题】Spring <form:select> 标签在 Spring mvc + Hibernate 应用程序中导致错误【英文标题】：Spring <form:select> tag causing error in Spring mvc + Hibernate app 【发布时间】：2013-12-26 20:55:19 【问题描述】：首先，我想说的是，我已经在整个 Internet 和 SO 上搜索了解决方案，但没有找到针对这种特殊情况的解决方案。我只是在学习 java web 编程。我正在制作简单的 mvc 应用程序，用于将教师添加到 mysql 数据库。 DB只有3个表：'teacher'、'title'和连接表'teacher_title'。 'title' 是一个查找表，具有 'title_id' / 'title_description' 值。 在我的 jsp 页面中，我有用于选择教师职称（例如博士、理学硕士等）的下拉列表、用于输入教师名字和姓氏的 2 个输入字段以及一个提交/保存按钮。
这是我的控制器：
/**
* Handles and retrieves the add teacher page
*/
@RequestMapping(value="/add", method = RequestMethod.GET)
public String getAddTeacher(Model model)
logger.debug("Received request to show add teacher page");
// Add to model
model.addAttribute("teacherAttribute", new Teacher());
model.addAttribute("titleList", titleService.getAll());
return "addTeacher";
/**
* Adds a new teacher by delegating the processing to TeacherService.
* Displays a confirmation JSP page
*/
@RequestMapping(value="/add", method = RequestMethod.POST)
public String postAddTeacher(@RequestParam(value = "id") Integer titleId,
@ModelAttribute("teacherAttribute") Teacher teacher)
logger.debug("Received request to add new teacher");
// Call TeacherService to do the actual adding
teacherService.add(titleId, teacher);
return "addTeacherSuccess";
这是 addTeacher.jsp 页面的重要部分：
<c:url var="saveUrl" value="/essays/main/teacher/add?id=titleId" />
<form:form modelAttribute="teacherAttribute" method="POST" action="$saveUrl">
<form:label path="title">Title:</form:label>
<form:select path="title" id="titleSelect">
<form:option value="0" label="Select" />
<form:options items="$titleList" itemValue="titleId" itemLabel="titleDescription" />
</form:select>
...
这是教师实体：
@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "TEACHER_ID")
private Integer techerId;
@Column(name = "FIRST_NAME", length = 50)
private String firstName;
@Column(name = "LAST_NAME", length = 50)
private String lastName;
@ManyToOne(cascade = CascadeType.PERSIST, CascadeType.MERGE, fetch=FetchType.EAGER)
@JoinTable(name="teacher_title",
joinColumns = @JoinColumn(name="TEACHER_ID"),
inverseJoinColumns = @JoinColumn(name="TITLE_ID")
)
private Title title;
// getters and setters
这是标题实体：
@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "TITLE_ID")
private Integer titleId;
@Column(name = "TITLE_DESCRIPTION", length = 10)
private String titleDescription;
// getters and setters
为了以防万一，这些分别是教师和职称服务：
/**
* Adds new teacher
*/
public void add(Integer titleId, Teacher teacher)
logger.debug("Adding new teacher");
Session session = sessionFactory.getCurrentSession();
// Retrieve existing title via id
Title existingTitle = (Title) session.get(Title.class, titleId);
// Add title to teacher
teacher.setTitle(existingTitle);
// Persists to db
session.save(teacher);
.
/**
* Retrieves a list of titles
*/
public List<Title> getAll()
logger.debug("Retrieving all titles");
Session session = sessionFactory.getCurrentSession();
Query query = session.createQuery("FROM Title");
List<Title> titleList = castList(Title.class, query.list());
return titleList;
public static <T> List<T> castList(Class<? extends T> clazz, Collection<?> c)
List<T> r = new ArrayList<T>(c.size());
for(Object o: c)
r.add(clazz.cast(o));
return r;
/**
* Retrieves a single title
*/
public Title get(Integer titleId)
logger.debug("Retrieving single title");
Session session = sessionFactory.getCurrentSession();
// Retrieve existing title
Title title = (Title) session.get(Title.class, titleId);
return title;
到目前为止，我设法理解的是问题出在我的 jsp 中的 select 标记上。当我注释掉选择标签并手动输入参数时（例如 URL?id=1），保存到数据库就可以了。否则我会收到以下错误：“HTTP 状态 400 - 客户端发送的请求在语法上不正确。”。我也在网上搜索过这个错误，但没有找到适用的解决方案。
我无法确定我在哪里犯了错误。提前谢谢你。
更新：
这是添加新教师的新控制器方法，其中@RequestParam 的value 属性从id 更改为title：
@RequestMapping(value="/add", method = RequestMethod.POST)
public String postAddTeacher(@RequestParam(value = "title") Integer titleId,
@ModelAttribute("teacherAttribute") Teacher teacher)
logger.debug("Received request to add new teacher");
// Call TeacherService to do the actual adding
teacherService.add(titleId, teacher);
// This will resolve to /WEB-INF/jsp/addTeacherSuccess.jsp
return "addTeacherSuccess";
这是新的 addTeacher.jsp，其中 ?id=titleId 已从 URL 中删除：
<c:url var="saveUrl" value="/essays/main/teacher/add" />
<form:form modelAttribute="teacherAttribute" method="POST" action="$saveUrl">
<form:label path="title">Title:</form:label>
<form:select path="title" id="titleSelect">
<form:option value="0" label="Select" />
<form:options items="$titleList" itemValue="titleId" itemLabel="titleDescription" />
</form:select>
...
仍然出现与以前相同的错误。
这是我遇到的错误（我不明白）：
[TRACE] [http-bio-8080-exec-7 11:10:38] (InvocableHandlerMethod.java:getMethodArgumentValues:166) Error resolving argument [1] [type=com.jovana.domain.Teacher]
HandlerMethod details:
Controller [com.jovana.controller.MainController]
Method [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]
org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:110)
at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:77)
at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:162)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:123)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
[TRACE] [http-bio-8080-exec-7 11:10:38] (InvocableHandlerMethod.java:getMethodArgumentValues:166) Error resolving argument [1] [type=com.jovana.domain.Teacher]
HandlerMethod details:
Controller [com.jovana.controller.MainController]
Method [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]
org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
at org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:110)
at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:77)
at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:162)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:123)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (AbstractHandlerExceptionResolver.java:resolveException:132) Resolving exception from handler [public java.lang.String com.jovana.controller.MainController.postAddTeacher(java.lang.Integer,com.jovana.domain.Teacher)]: org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 1 errors
Field error in object 'teacherAttribute' on field 'title': rejected value [4]; codes [typeMismatch.teacherAttribute.title,typeMismatch.title,typeMismatch.com.jovana.domain.Title,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [teacherAttribute.title,title]; arguments []; default message [title]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'com.jovana.domain.Title' for property 'title'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.jovana.domain.Title] for property 'title': no matching editors or conversion strategy found]
[DEBUG] [http-bio-8080-exec-7 11:10:38] (DispatcherServlet.java:processDispatchResult:999) Null ModelAndView returned to DispatcherServlet with name 'spring': assuming HandlerAdapter completed request handling
[DEBUG] [http-bio-8080-exec-7 11:10:38] (DispatcherServlet.java:processDispatchResult:999) Null ModelAndView returned to DispatcherServlet with name 'spring': assuming HandlerAdapter completed request handling
[TRACE] [http-bio-8080-exec-7 11:10:38] (FrameworkServlet.java:resetContextHolders:1028) Cleared thread-bound request context: org.apache.catalina.connector.RequestFacade@5f57b190
[TRACE] [http-bio-8080-exec-7 11:10:38] (FrameworkServlet.java:resetContextHolders:1028) Cleared thread-bound request context: org.apache.catalina.connector.RequestFacade@5f57b190
[DEBUG] [http-bio-8080-exec-7 11:10:38] (FrameworkServlet.java:processRequest:966) Successfully completed request
[DEBUG] [http-bio-8080-exec-7 11:10:38] (FrameworkServlet.java:processRequest:966) Successfully completed request
[TRACE] [http-bio-8080-exec-7 11:10:38] (AbstractApplicationContext.java:publishEvent:332) Publishing event in WebApplicationContext for namespace 'spring-servlet': ServletRequestHandledEvent: url=[/testLookupTable/essays/main/teacher/add]; client=[0:0:0:0:0:0:0:1]; method=[POST]; servlet=[spring]; session=[72089007DB0E4468BA90CDA44FCA8CC0]; user=[null]; time=[144ms]; status=[OK]
[TRACE] [http-bio-8080-exec-7 11:10:38] (AbstractApplicationContext.java:publishEvent:332) Publishing event in WebApplicationContext for namespace 'spring-servlet': ServletRequestHandledEvent: url=[/testLookupTable/essays/main/teacher/add]; client=[0:0:0:0:0:0:0:1]; method=[POST]; servlet=[spring]; session=[72089007DB0E4468BA90CDA44FCA8CC0]; user=[null]; time=[144ms]; status=[OK]
[TRACE] [http-bio-8080-exec-7 11:10:38] (AbstractApplicationContext.java:publishEvent:332) Publishing event in Root WebApplicationContext: ServletRequestHandledEvent: url=[/testLookupTable/essays/main/teacher/add]; client=[0:0:0:0:0:0:0:1]; method=[POST]; servlet=[spring]; session=[72089007DB0E4468BA90CDA44FCA8CC0]; user=[null]; time=[144ms]; status=[OK]
[TRACE] [http-bio-8080-exec-7 11:10:38] (AbstractApplicationContext.java:publishEvent:332) Publishing event in Root WebApplicationContext: ServletRequestHandledEvent: url=[/testLookupTable/essays/main/teacher/add]; client=[0:0:0:0:0:0:0:1]; method=[POST]; servlet=[spring]; session=[72089007DB0E4468BA90CDA44FCA8CC0]; user=[null]; time=[144ms]; status=[OK]
解决方案（谢谢storm_buster）正在将这个添加到控制器中：
@InitBinder
public void initBinder(WebDataBinder binder, WebRequest request)
binder.registerCustomEditor(Title.class, "title", new PropertyEditorSupport()
@Override
public void setAsText(String text)
setValue((text.equals(""))?null:titleService.getTitle(Integer.parseInt((String)text)));
);
结束！
【问题讨论】：
你应该发布一些不太冗长的问题，这真的很难理解。您可以从删除不必要的 getter 和 setter 开始... 我猜add?id=titleId 应该是add?id=$titleId？
@Bart 我试过了，但发送的是add?id= 。似乎$titleId 是空的（就像从列表中选择项目甚至不起作用）。知道为什么吗？
在 org.springframework 上将日志级别设置为 TRACE 时会输出什么？它应该显示出了什么问题
【参考方案1】：
您收到此错误是因为您正在使用
@ModelAttribute("teacherAttribute") 老师老师)
Spring 无法将您的 requestParam “title”（即字符串）转换为属于教师实体的 Title 类。
您有两个解决方案： 1-将此添加到您的控制器中
@InitBinder
public void initBinder(WebDataBinder binder, WebRequest request)
binder.registerCustomEditor(Title.class, "title", new PropertyEditorSupport()
@Override
public void setAsText(String text)
setValue((text.equals(""))?null:titleService.getTitle(Integer.parseInt((String)text)));
);
2- 将您的请求映射修改为：
@RequestMapping(value="/add", method = RequestMethod.POST)
public String postAddTeacher(@RequestParam(value = "title") Integer titleId,
@RequestParam("teacherAttribute") Integer teacherId)
并添加一个新接口：
teacherService.add(titleId, teacherId);
【讨论】：
'@storm_buster' 它不会让我在评论中标记你，所以我不得不添加引号只是为了显示你的用户名。另外，谢谢您的解释...除了接受您的回答，我还能为您的声誉评分做些什么吗？我无权投票给答案...：/ @just_a_girl 我认为没关系。很高兴它起作用了。随便问什么。【参考方案2】：<c:url var="saveUrl" value="/essays/main/teacher/add?id=titleId" />
您不需要手动将参数写为?id=titleId，它会自动添加。在这种情况下，在请求正文中（因为它是 POST 请求）。
另外，表单标签中的path 属性和控制器属性中的@RequestParam 中的value 必须相同。所以写，比如@RequestParam(value = "title") Integer titleId
【讨论】：
好的，如果我在jsp中丢失了?id=titleId，并且在处理程序方法中丢失了@RequestParam(value="id") Integer titleId，我如何访问控制器中的titleId（因为我需要通过它给教师服务）？很抱歉问了这样一个初学者的问题... 当你给<form:select path="title" .. 和@RequestParam(value = "title") .. 赋予相同的名字时，Spring 将绑定值并放入你的titleId 变量中
我明白了，我按照你说的做了（删除了?id=titleId 并将@RequestParam 中的'id' 重命名为'title'）但我仍然收到同样的错误（“客户端发送的请求是语法不正确。") :(
你知道如何通过<form:options ...> 标签告诉控制器itemValue="titleId"，我相信这就是它所期望的吗？还是我错了？ BTW Max Vasileusky 我不知道如何在我的评论中标记你，'@Max Vasileusky' 不起作用......
itemValue 用于填充列表。如果下拉列表没问题，那么 itemValue 没问题 :) 如果您使用的是 Chrome，您可以按 F12，打开网络选项卡，从页面发送请求，看看它的参数是否符合预期。 （其他浏览器也有类似的工具）以上是关于Spring <form:select> 标签在 Spring mvc + Hibernate 应用程序中导致错误的主要内容，如果未能解决你的问题，请参考以下文章
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