package com.hy.springmvc.entities;

import org.springframework.core.convert.converter.Converter;

import com.google.gson.Gson;

public class DepartmentConvertor implements Converter<String, Department> {

 @Override
 public Department convert(String source) {
  System.out.println("com.hy.springmvc.entities.DepartmentConvertor: "
    + source);
  Department department = new Gson().fromJson(source, Department.class);
  return department;
 }

}

<bean id="conversionService"
  class="org.springframework.context.support.ConversionServiceFactoryBean">
  <property name="converters">
   <list>
    <bean class="com.hy.springmvc.entities.DepartmentConvertor"></bean>
   </list>
  </property>
 </bean>

<mvc:annotation-driven conversion-service="conversionService">
</mvc:annotation-driven>