@Vaild is not working

Question

I want to check size validation for studentHobby object and i am using @Size annotation and Using @valid annotation.

I am providing less than the value defined in @Size annotation but still I am getting the result instead of error.

I tried things but didn't come with solutions.

StudentAdmissionController.java

package com.diwakar;

import javax.validation.Valid;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
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;


@Controller
public class StudentAdmissionController {

    @InitBinder
    public void initBinder(WebDataBinder binder) {
        //binder.setDisallowedFields(new String[] {"studentMobile"});
        //SimpleDateFormat date = new SimpleDateFormat("dd**MM**yyyy");
        //binder.registerCustomEditor(Date.class, "studentDOB", new CustomDateEditor(date, false)); 
        binder.registerCustomEditor(String.class, "studentName", new StudentNameEditor());
    }

    @RequestMapping(value="/admission.html", method = RequestMethod.GET)
    public ModelAndView getAdmissionForm() {

        ModelAndView model =  new ModelAndView("AdmissionForm");
        //model.addObject("headerMessage", "Diwakar College of Engineering.!!");
        return model;
    }

    @RequestMapping(value="/submitForm", method =  RequestMethod.POST)
    public ModelAndView submitAdmissionForm(@Valid @ModelAttribute("st1") Student st1, BindingResult result) {

        if (result.hasErrors()) {
            ModelAndView model =  new ModelAndView("AdmissionForm");
            return model;
        }

        ModelAndView model = new ModelAndView("AdmissionSuccess");
        //model.addObject("headerMessage", "Diwakar College of Engineering.!!");
        return model;
    }   

    @ModelAttribute
    public void addCommonMessage(Model model) {
        model.addAttribute("headerMessage", "Diwakar College of Engineering.!!");
    }

Student.java

package com.diwakar;

import java.util.ArrayList;
import java.util.Date;

import javax.validation.constraints.Size;

public class Student {

    private String studentName;

    @Size(min=3, max=10)
    private String studentHobby;

    private Long studentMobile;

    private Date studentDOB;
    private ArrayList<String> studentSkills;
    private Address studentAddress;

    public String getStudentName() {
        return studentName;
    }
    public void setStudentName(String studentName) {
        this.studentName = studentName;
    }
    public String getStudentHobby() {
        return studentHobby;
    }
    public void setStudentHobby(String studentHobby) {
        this.studentHobby = studentHobby;
    }
    public Long getStudentMobile() {
        return studentMobile;
    }
    public void setStudentMobile(Long studentMobile) {
        this.studentMobile = studentMobile;
    }
    public Date getStudentDOB() {
        return studentDOB;
    }
    public void setStudentDOB(Date studentDOB) {
        this.studentDOB = studentDOB;
    }
    public ArrayList<String> getStudentSkills() {
        return studentSkills;
    }
    public void setStudentSkills(ArrayList<String> studentSkills) {
        this.studentSkills = studentSkills;
    }
    public Address getStudentAddress() {
        return studentAddress;
    }
    public void setStudentAddress(Address studentAddress) {
        this.studentAddress = studentAddress;
    }   
}

spring-dispatcher-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
                        http://www.springframework.org/schema/beans/spring-beans.xsd
                        http://www.springframework.org/schema/context
                        http://www.springframework.org/schema/context/spring-context.xsd
                        http://www.springframework.org/schema/mvc
                        http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">



<!--      <bean id="HandlerMapping" class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping" />
          <bean name="/welcome.html" class="com.diwakar.HelloController" />  -->

     <context:component-scan base-package="com.diwakar" />
     <mvc:annotation-driven />

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

</beans>

Here is my admission page even though i am providing one one character it is giving me submit form instead of error. admission.html Page

This submit form i am getting after submitting value with 1 character. submitForm