How to Validate duplicate entries in database using struts1

Hi,

After submitting the form i have to validate the email id. If already exists in database i have to display an error message saying that email id already exist. I have written the code but its not working. Can any one help me. I have attached my code

jsp code
----------

<!DOCTYPE html>
<%@page contentType="text/html"%>
<%@page pageEncoding="UTF-8"%>

<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<%@ taglib uri="http://struts.apache.org/tags-logic" prefix="logic" %>
<%--<%@taglib uri="http://struts.apache.org/tags-tiles" prefix="tiles" %>--%>
<%--<%@taglib uri="/struts-tags" prefix="s" %>--%>
<html lang="en">
<body>

<section id="mainContent">
<article class="last">
<div class="inside">
<table id="login-form">
<html:form action="/NewUserForm" styleId="login-form">
<fieldset>
<div class="field">
<tr>
<td>
<bean:message key="newuser.title2"/>
</td>
<td>
<html:text property="firstname"/>
</td>
<td>
<html:errors property="firstname"/>
</td>
</tr>

</div>
<div class="field">
<tr>
<td>
<bean:message key="newuser.title3"/>
</td>
<td>
<html:text property="lastname"/>
</td>
<td>
<html:errors property="lastname"/>
</td>
</tr>

</div>
<div class="field">
<tr>
<td>
<bean:message key="newuser.title4"/>
</td>
<td>
<html:radio property="gender" value="Male">Male</html:radio>
<html:radio property="gender" value="Female">Female</html:radio>
</td>
<td>
<html:errors property="gender"/>
</td>
</tr>
<%--<s:radio name="" list="{'Male','Female'}"/>--%>
<%--<label for="checkbox">Remember me</label> <input type="checkbox" name="checkbox" id="checkbox">--%>
</div>
<div class="field">
<tr>
<td>
<bean:message key="newuser.title5"/>
</td>
<td>
<html:text property="dateofbirth"/>
</td>
<td>
<html:errors property="dateofbirth"/>
</td>
</tr>
<%--<s:date name="date" format="dd-mm-yyyy" />--%>
<%--<s:textfield/>--%>
</div>
<div class="field">
<tr>
<td>
<bean:message key="newuser.title6"/><sup>*</sup>
</td>
<td>
<html:text property="emailid"/>
</td>
<td>
<html:errors property="emailid"/>
</td>
</tr>

</div>
<div>
<tr>
<td>
<bean:message key="common.title1"/>
</td>
<td>
<html:text property="username"/>
</td>
<td>
<html:errors property="username"/>
</td>
</tr>

</div>
<div>
<tr>
<td>
<bean:message key="common.title2"/>
</td>
<td>
<html:password property="password"/>
</td>
<td>
<html:errors property="password"/>
</td>
</tr>

</div>
<div>
<tr>
<td>
<bean:message key="newuser.title7"/>
</td>
<td>
<html:password property="confirmpassword"/>
</td>
<td>
<html:errors property="confirmpassword"/>
</td>
</tr>

</div>

<div class="wrapper">
<tr>
<td colspan="3">
<html:submit value="REGISTER" styleId="submit"/>
</td>
</tr>

</div>
</fieldset>
</html:form>
</table>

</div>
</article>
</section>
</div>
</div>
</section>

<footer>
<div class="container">
<a href=""><bean:message key="common.title31"/></a> <bean:message key="common.title32"/> <a href=""><bean:message key="common.title33"/></a>
</div>
</footer>
</body>
</html>

action class
--------------

package classes.newuser;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionError;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionFormBean;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionRedirect;
import org.apache.struts.action.ActionServlet;
import org.apache.struts.validator.FieldChecks;
import org.apache.struts.validator.ValidatorPlugIn;
import org.apache.struts.validator.validwhen.ValidWhen;

public class NewUserAction extends org.apache.struts.action.Action {

private static final String SUCCESS = "success";

public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {

NewUserForm nsf=(NewUserForm)form;

String firstname=nsf.getFirstname();
String lastname=nsf.getLastname();
String gender=nsf.getGender();
String dateofbirth=nsf.getDateofbirth();
String emailid=nsf.getEmailid();
//String email=request.getParameter("emailid");
String username=nsf.getUsername();
String password=nsf.getPassword();
String confirmpassword=nsf.getConfirmpassword();

try{

String url="jdbc:mysql://localhost:3306/nemogroups";
Class.forName("com.mysql.jdbc.Driver");
Connection con= DriverManager.getConnection(url, "root" ,"root" );
Statement st=con.createStatement();

//String email=request.getParameter("emailid").toString();
System.out.println(emailid);
ResultSet rs=st.executeQuery("select emailid from registration where emailid='"+emailid+"'");
int count=0;
while(rs.next()){

String email=rs.getString("emailid");
System.out.println("email=============="+email);
count++;
}

if(count>0){

ActionErrors errors=new ActionErrors();
errors.add("emailid", new ActionMessage("NewUserForm.emailid.alreadyexists"));

}

else{

String insert="insert into registration(firstname,lastname,gender,dateofbirth,emailid,username,password,confirmpassword) values('"+firstname+"','"+lastname+"','"+gender+"','"+dateofbirth+"','"+emailid+"','"+username+"','"+password+"','"+confirmpassword+"')";
st.executeUpdate(insert);

}

}
catch (Exception e) {
// TODO: handle exception
System.out.println(e);
}
return mapping.findForward(SUCCESS);
}
/* public ActionErrors validate(ActionMapping mapping, HttpServletRequest request){

ActionErrors errors=new ActionErrors();

errors.add("emailid",new ActionError(error.emailid.wrong));
return errors;
}*/

}

action form
--------------

package classes.newuser;

import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionMapping;

public class NewUserForm extends org.apache.struts.validator.ValidatorForm {

private static final long serialVersionUID = 1L;
private String firstname=null;
private String lastname=null;
private String gender=null;
private String dateofbirth=null;
private String emailid=null;
private String username=null;
private String password=null;
private String confirmpassword=null;

public String getConfirmpassword() {
return confirmpassword;
}

public String getDateofbirth() {
return dateofbirth;
}

public String getEmailid() {
return emailid;
}

public String getFirstname() {
return firstname;
}

public String getGender() {
return gender;
}

public String getLastname() {
return lastname;
}

public String getPassword() {
return password;
}

public String getUsername() {
return username;
}

public void setConfirmpassword(String confirmpassword) {
this.confirmpassword = confirmpassword;
}

public void setDateofbirth(String dateofbirth) {
this.dateofbirth = dateofbirth;
}

public void setEmailid(String emailid) {
this.emailid = emailid;
}

public void setFirstname(String firstname) {
this.firstname = firstname;
}

public void setGender(String gender) {
this.gender = gender;
}

public void setLastname(String lastname) {
this.lastname = lastname;
}

public void setPassword(String password) {
this.password = password;
}

public void setUsername(String username) {
this.username = username;
}

public void reset(ActionMapping mapping,HttpServletRequest request){

this.firstname=null;
this.lastname=null;
this.gender=null;
this.dateofbirth=null;
this.emailid=null;
this.username=null;
this.password=null;
this.confirmpassword=null;

}

/*public ActionErrors validate(ActionMapping mapping,HttpServletRequest request){

ActionErrors errors=new ActionErrors();

return errors;
}*/
}

Thanks in advance
Parthiban

this code is validating the email id but the error message is not displayed saying that email id already exists. can any one help me.