Não estou conseguindo instanciar a classe SendMail

package controller;

import model.SendMail;
import model.dao.AlunoDAO;
import model.dao.FuncionarioDAO;
import model.dao.ProfessorDAO;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.swing.JOptionPane;
import org.apache.commons.lang.RandomStringUtils;

public class RegistroServlet extends HttpServlet {

    /*vei enviar um email de confirmação de inscrição,
     para a pessoa que acabou de efetuar o registro*/
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {

            //recupera dos dados do primeiro registro
            String email = request.getParameter("email");
            String matricula = request.getParameter("matricula");
            
            //gera a senha aleatória
            String alePWD = RandomStringUtils.randomAlphanumeric(6);
            
            String matricula1 = matricula.substring(0,3);
            
            if ( matricula1.equals( "PRO" ) )
            {
                ProfessorDAO.inserirRegistro(matricula, email, alePWD);
                
                JOptionPane.showMessageDialog(null, "Cadastro efetuado com sucesso! "
                    + "Verifique o email para completar o seu cadastro");
            
            response.sendRedirect("index.jsp");
            
            }
            else if ( matricula1.equals( "ALU" ) )
            {
                //faz o primeiro registro
                AlunoDAO.inserirRegistro(matricula, email, alePWD);
                
                SendMail sm = new SendMail();
                
                //envia o email
                //SendMail sm = new SendMail();
                //sm.sendMail("[email removido]", email, "Registro efetuado com sucesso", "sua senha aleatória é:"+ alePWD);
                
                JOptionPane.showMessageDialog(null, "Cadastro efetuado com sucesso! "
                    + "Verifique o email para completar o seu cadastro");
            
            response.sendRedirect("index.jsp");
            
            }    
            else if ( matricula1.equals( "FUN" ) )
            {
                FuncionarioDAO.inserirRegistro(matricula, email, alePWD);
                
                JOptionPane.showMessageDialog(null, "Cadastro efetuado com sucesso! "
                    + "Verifique o email para completar o seu cadastro");
            
            response.sendRedirect("index.jsp");
            }
            else{
                JOptionPane.showMessageDialog(null, "Insira uma matrícula válida. Consulte a sua secretaria para obte-la.");
                
                response.sendRedirect("index.jsp");
            }
            
            //SendMail sm = new SendMail();
            /*sm.sendMail("[email removido]", "[email removido]", "Complete o seu cadastro", 
                    "Email cadastrado com sucesso<br>"
                    + "Complete o seu cadastro por favor");*/
            
        } finally { 
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
    
}

package model;

import java.util.Properties;
import javax.mail.Message;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class SendMail {

    private String mailSMTPServer;
    private String mailSMTPServerPort;

    /*quando instanciar um objeto já será atribuido o servidor SMTP do GAMIL
     e a porta usada por ele
     */
    
    SendMail()
    {//Para o GMAIL
        mailSMTPServer = "smtp.gmail.com";
        mailSMTPServerPort = "465";
    }
    
    /*
     caso queira mudar o servidor e a porta, só enviar para o construtor
     * os valores cmo string
     */
    SendMail(String mailSMTPServer, String mailSMTPServerPort)
    {
        this.mailSMTPServer = mailSMTPServer;
        this.mailSMTPServerPort = mailSMTPServerPort;
    }

    public void sendMail(String from, String to, String subject, String message)
    {
        Properties props = new Properties();

        //proxy
        props.setProperty("proxySet","true");
        props.setProperty("socksProxyHost", "192.168.155.1");
        props.setProperty("socksProxyPort", "1080");

        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.host", mailSMTPServer);
        props.put("mai.smtp.auth", "true");
        props.put("mail.smtp.user", from);
        props.put("mail.debug", "true");
        props.put("mail.smtp.port", mailSMTPServerPort);
        props.put("mail.smtp.socketFactory.port", mailSMTPServerPort);
        props.put("mail.smtp.socketFactory.class",
                "javax.net.ssl.SSLSocketFactory");

        SimpleAuth auth = null;
        auth = new SimpleAuth("[email removido]","sistemaFIRJAN");

        Session session = Session.getDefaultInstance(props, auth);
        session.setDebug(true);

        Message msg = new MimeMessage(session);

        try
        {
            msg.setRecipient(Message.RecipientType.TO, new InternetAddress(to));
            msg.setFrom(new InternetAddress(from));
            msg.setSubject(subject);
            msg.setContent(message, "text/html");

        }catch (Exception e)
        {
            System.out.println(">> Erro: Completar Mensagem");
            e.printStackTrace();
        }

        Transport tr;
        try
        {
            tr = session.getTransport("smtp");
            tr.connect(mailSMTPServer, "[email removido]","sistemaFIRJAN");
            msg.saveChanges();
            tr.sendMessage(msg, msg.getAllRecipients());
            tr.close();
        }catch( Exception e )
        {
            System.out.println( ">> Erro: Completar Mensagem" );
            e.printStackTrace();
        }


    }

}