jQuery validate method and displaying messages

I am using Spring MVC, jQuery validate plugin and I am trying to display custom error messages. My code is working fine. The url i specified in remote: connects to my MVC controller. The logic in the controller executes fine. The jQuery files are added correctly too.

My problem is how do I get the error message in messages: to display in my JSP file. I have added my code. (Note: I am not sure if I understand the remote function in the jQuery file. I think you have to return true or false. I am going on the jQuery documentation.). Perhaps someone can help. Thanks.

register.jsp

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags" %>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>

<c:if test="${not empty message}">
    <div id="message" class="${message.type}">${message.message}</div>
</c:if>

<script type="text/javascript">
$(document).ready(function(){
    $("#reg").validate({
        rules: {
            email: {
                required: true,
                email: true,
                remote: 'clientside/emailsearch'
            }      
        },
        messages:{
            email:{
                required: "You need an email",
                email: "This is not valid",
                remote: "Someone has this email already!"
                
            }
        }
    });
});    
</script>

<form:form id="reg" method="POST" modelAttribute="farmer">
    <fieldset>
        <legend><spring:message code="label_register"/></legend>
        <table>
            <tr><td><form:label path="herdNo" cssErrorClass="error"><spring:message code="label_farmer_herdno" /></form:label></td><td><form:input id="herdNo" path="herdNo" /></td><td class="error"><form:errors path="herdNo" /></td></tr>        
            <tr><td><form:label path="name" cssErrorClass="error"><spring:message code="label_farmer_name" /></form:label></td><td><form:input id="name" path="name" /></td><td><form:errors path="name"/></td></tr>
            <tr><td><form:label path="addressLine1" cssErrorClass="error"><spring:message code="label_farmer_address1" /></form:label></td><td><form:input id="addressLine1" path="addressLine1" /></td><td><form:errors path="addressLine1"/></td></tr>
            <tr><td><form:label path="addressLine2" cssErrorClass="error"><spring:message code="label_farmer_address2" /></form:label></td><td><form:input id="addressLine2" path="addressLine2" /></td><td><form:errors path="addressLine2"/></td></tr>
            <tr><td><form:label path="addressLine3" cssErrorClass="error"><spring:message code="label_farmer_address3" /></form:label></td><td><form:input id="addressLine3" path="addressLine3" /></td><td><form:errors path="addressLine3"/></td></tr>
            <tr><td><form:label path="addressLine4" cssErrorClass="error"><spring:message code="label_farmer_address4" /></form:label></td><td><form:input id="addressLine4" path="addressLine4" /></td><td><form:errors path="addressLine4"/></td></tr>
            <tr><td><form:label path="phoneNo" cssErrorClass="error"><spring:message code="label_farmer_phoneno" /></form:label></td><td><form:input id="phoneNo" path="phoneNo" /></td><td><form:errors path="phoneNo"/></td></tr>
        </table>
    </fieldset>
    <fieldset>
        <legend><spring:message code="farmer_login_details"/></legend>
        <table>
            <tr><td><form:label path="username" cssErrorClass="error"><spring:message code="label_farmer_username" /></form:label></td><td><form:input id="username" path="username" /></td><td><form:errors path="username"/></td></tr>
            <tr><td><form:label path="password" cssErrorClass="error"><spring:message code="label_farmer_password" /></form:label></td><td><form:password id="password" path="password" /></td><td><form:errors path="password"/></td></tr>
            <tr><td><form:label path="email" cssErrorClass="error"><spring:message code="label_farmer_email" /></form:label></td><td><form:input id="email" path="email" /></td><td><form:errors path="email"/></td></tr>
        </table>
    </fieldset>
    <button id="save"><spring:message code="button_save"/></button>
</form:form>

MVC controller

package com.jamesanthony527.herdmanager.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import com.jamesanthony527.herdmanager.service.FarmerService;

@RequestMapping("/clientside")
@Controller
public class ClientJsController {
    
    private static final Logger logger = LoggerFactory.getLogger(ClientJsController.class);

    
    @Autowired
    private FarmerService farmService;
    
    @RequestMapping(value="/emailsearch", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
    public @ResponseBody boolean checkMail(@RequestParam String email){ 
        
        logger.info("Well got to the method!");
        
        logger.info(email);
        
        if(farmService.findByEmail(email) != null) {
            
            logger.info("The query worked");
            return true;
        }
        else{
            return false;
        }
        
    }
}