Model view controller 在Spring3注释中，jsr303既不获取BindingResult，也不获取bean名称的普通目标对象'；数据格式'；

使用带注释的spring 3实现一个简单的jsr303验证，当post发现缺少的元素时，我会得到以下结果：

java.lang.IllegalStateException:bean名称“dataForm”的BindingResult和普通目标对象都不能作为请求属性使用

控制器看起来是这样的：

@Controller
@SessionAttributes
@RequestMapping( "/dataentry.html" )
public class EnterDataController
{
  @RequestMapping( method = RequestMethod.GET )
  public String enterNewDataHandler( Map model )
  {
    DataEntryForm dataForm = new DataEntryForm();
    model.put( "dataForm", dataForm );
    return ( "dataentry" );
  }

  @RequestMapping( method = RequestMethod.POST )
  public String addData( @Valid DataEntryForm dataForm,
                           BindingResult          result,
                           Map                    model )
  {
    if ( result.hasErrors() ) { return ( "dataentry" ); }

    ... code for saving data ...
  }
}

public class DataEntryForm
{
  @NotNull
  private Double dataAmount;

  @NotNull
  @Temporal(value=TemporalType.TIMESTAMP)
  private Date dataDate;

  ... sets and gets ...
}

<form:form method="post"
           commandName="dataForm"
           action="dataentry.html">
  <table>
  <tr>
    <td><form:label path=dataAmount">Data</form:label></td>
    <td><form:input path="dataAmount"/></td>
    <td><div class="error"><form:errors path="dataAmount"/></div></td>
  </tr>
  <tr>
    <td><form:label path="dataDate">Date</form:label></td>
    <td><form:input path="dataDate"/></td>
    <td><div class="error"><form:errors path="dataDate"/></div></td>
  </tr>
  <tr>
    <td colspan="2"><input type="submit" value="Add Data"/></td>
  </tr>
</table>
</form:form>

表单看起来是这样的：

@Controller
@SessionAttributes
@RequestMapping( "/dataentry.html" )
public class EnterDataController
{
  @RequestMapping( method = RequestMethod.GET )
  public String enterNewDataHandler( Map model )
  {
    DataEntryForm dataForm = new DataEntryForm();
    model.put( "dataForm", dataForm );
    return ( "dataentry" );
  }

  @RequestMapping( method = RequestMethod.POST )
  public String addData( @Valid DataEntryForm dataForm,
                           BindingResult          result,
                           Map                    model )
  {
    if ( result.hasErrors() ) { return ( "dataentry" ); }

    ... code for saving data ...
  }
}

public class DataEntryForm
{
  @NotNull
  private Double dataAmount;

  @NotNull
  @Temporal(value=TemporalType.TIMESTAMP)
  private Date dataDate;

  ... sets and gets ...
}

<form:form method="post"
           commandName="dataForm"
           action="dataentry.html">
  <table>
  <tr>
    <td><form:label path=dataAmount">Data</form:label></td>
    <td><form:input path="dataAmount"/></td>
    <td><div class="error"><form:errors path="dataAmount"/></div></td>
  </tr>
  <tr>
    <td><form:label path="dataDate">Date</form:label></td>
    <td><form:input path="dataDate"/></td>
    <td><div class="error"><form:errors path="dataDate"/></div></td>
  </tr>
  <tr>
    <td colspan="2"><input type="submit" value="Add Data"/></td>
  </tr>
</table>
</form:form>

jsp表单部分如下所示：

@Controller
@SessionAttributes
@RequestMapping( "/dataentry.html" )
public class EnterDataController
{
  @RequestMapping( method = RequestMethod.GET )
  public String enterNewDataHandler( Map model )
  {
    DataEntryForm dataForm = new DataEntryForm();
    model.put( "dataForm", dataForm );
    return ( "dataentry" );
  }

  @RequestMapping( method = RequestMethod.POST )
  public String addData( @Valid DataEntryForm dataForm,
                           BindingResult          result,
                           Map                    model )
  {
    if ( result.hasErrors() ) { return ( "dataentry" ); }

    ... code for saving data ...
  }
}

public class DataEntryForm
{
  @NotNull
  private Double dataAmount;

  @NotNull
  @Temporal(value=TemporalType.TIMESTAMP)
  private Date dataDate;

  ... sets and gets ...
}

<form:form method="post"
           commandName="dataForm"
           action="dataentry.html">
  <table>
  <tr>
    <td><form:label path=dataAmount">Data</form:label></td>
    <td><form:input path="dataAmount"/></td>
    <td><div class="error"><form:errors path="dataAmount"/></div></td>
  </tr>
  <tr>
    <td><form:label path="dataDate">Date</form:label></td>
    <td><form:input path="dataDate"/></td>
    <td><div class="error"><form:errors path="dataDate"/></div></td>
  </tr>
  <tr>
    <td colspan="2"><input type="submit" value="Add Data"/></td>
  </tr>
</table>
</form:form>

我以前有过这个问题。我认为，除了使用
@Valid
之外，还必须使用
@modeldattribute（“dataForm”）
，以便它知道如何将表单映射到DataEntryForm对象

  @RequestMapping( method = RequestMethod.POST )
  public String addData( @ModelAttribute("dataForm") @Valid DataEntryForm dataForm,
                       BindingResult          result,
                       Map                    model )
  {
      if ( result.hasErrors() ) { return ( "dataentry" ); }

      ... code for saving data ...
  }

看起来有点难看。我有点希望这两个注释能以某种方式结合起来
 我在早些时候实现了这个建议，它确实起了作用，但是我尝试的几个示例应用程序没有使用@modeldattribute，运行良好，没有错误，因此这里发生的一些事情仍然没有意义。Thanks@sldahlin：同意您的意见，控制器中的modelattribute是不需要的。但若不使用model属性，则必须以某种方式向Spring展示如何解析对象。尝试在您的表单中添加modelAttribute=“dataAmount”Tag我知道它已经存在4个多月了，但这个答案解决了我的问题，谢谢！