Spring3 MVC：验证不起作用

性别验证无效。即使在性别文本字段中未输入任何值，表单也会成功验证而不会产生任何错误。

The gender validation is not working. Even if no values are entered in the gender text field, the form is getting validated successfully without throwing any error.

以下是Employee类：

Below is the Employee class:

@Size(min=2,max=10)
private String gender;

// Setters and Getters

以下是Controller方法：

Below is the Controller method:

@RequestMapping(value="done", method = RequestMethod.POST)
public String validateForm(@Valid Employee employee, BindingResult result, ModelMap m){
    if(result.hasErrors()){
        System.out.println("Validation Failed!!!");
        return "main";
    }else{
        System.out.println("Validation Succeeded!!!");
        return "done";
    }
}

以下是上下文文件：

<context:annotation-config />
<context:component-scan
    base-package="com.XXX" />

<bean id="viewResolver"
    class="org.springframework.web.servlet.view.UrlBasedViewResolver">
    <property name="viewClass"
        value="org.springframework.web.servlet.view.JstlView" />
    <property name="prefix" value="/WEB-INF/pages/" />
    <property name="suffix" value=".jsp" />
</bean>

以下是jsp文件：

<tr>
            <td>
                Gender:
            </td>
            <td>
                <form:input path="gender"/>
                <form:errors path="gender" cssStyle="color: red;"/>
            </td>
        </tr>

我无法找到丢失的东西，但它有些愚蠢。请帮助。

I am not able to find out whats missing but its something silly. Please help.