Untitled

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
     pageEncoding="ISO-8859-1"%>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
    <title>Login</title>
</head>
<body>
    <form action="loginServlet" method="post">
        <fieldset style="width: 300px">
            <legend> Login </legend>
            <table>
                <tr>
                    <td>Usuario</td>
                    <td><input type="text" name="usuario" required="required" /></td>
                </tr>
                <tr>
                    <td>Senha</td>
                    <td><input type="password" name="senha" required="required" /></td>
                </tr>
                <tr>
                    <td><input type="submit" value="Login" /></td>
                </tr>
            </table>
        </fieldset>
    </form>
</body>
</html>

package com.amzi.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class LoginDao {

public static boolean validate(String nome, String senha) {
    boolean status = false;
    Connection conn = null;
    PreparedStatement pst = null;
    ResultSet rs = null;

    String url = "jdbc:mysql://localhost:8095/";
    String dbName = "locadora";
    String driver = "com.mysql.jdbc.Driver";
    String userName = "root";
    String password = "123";
    try {
        Class.forName(driver).newInstance();
        conn = DriverManager
                .getConnection(url + dbName, userName, password);

        pst = conn
                .prepareStatement("select * from tab_usuarios where user=? and pw_user=?");
        pst.setString(1, nome);
        pst.setString(2, senha);

        rs = pst.executeQuery();
        status = rs.next();

    } catch (ClassNotFoundException | IllegalAccessException | InstantiationException | SQLException e) {
        System.out.println(e);
    } finally {
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
            }
        }
        if (pst != null) {
            try {
                pst.close();
            } catch (SQLException e) {
            }
        }
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
            }
        }
    }
    return status;
}
}

package com.amzi.servlets;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.amzi.dao.LoginDao;

public class LoginServlet extends HttpServlet {

private static final long serialVersionUID = 1L;

/**
 *
 * @param request
 * @param response
 * @throws ServletException
 * @throws IOException
 */
@Override
public void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

    response.setContentType("text/html");
    try (PrintWriter out = response.getWriter()) {
        String n = request.getParameter("usuario");
        String p = request.getParameter("senha");

        HttpSession session = request.getSession(false);
        if (session != null) {
            session.setAttribute("name", n);
        }

        if (LoginDao.validate(n, p)) {
            System.out.println("Senha correta!");
            RequestDispatcher rd = request.getRequestDispatcher("welcome.jsp");
            rd.forward(request, response);
        } else {
            out.print("<p style="color:red">Desculpe, usuario ou senha incorretos.</p>");
            RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
            rd.include(request, response);
        }
    }
}
}