Untitled

`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 username, String password) {
    boolean status = false;
    Connection conn = null;
    PreparedStatement pst = null;
    ResultSet rs = null;

    String url = "jdbc:mysql://localhost:3306/";
    String dbName = "info";
    String driver = "com.mysql.jdbc.Driver";
    String userName = "root";
    String passsword = "azerty";
    try {
           Class.forName(driver).newInstance();
           conn = DriverManager.getConnection(url+dbName, userName,passsword);
           pst = conn.prepareStatement("select * from users where username=? and password=?");
           pst.setString(1, username);
           pst.setString(2, password);
           rs = pst.executeQuery();
           status = rs.next();}
    catch (ClassNotFoundException | InstantiationException | IllegalAccessException | 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;

    }

    }`

enter code here
   import java.io.IOException;
    import java.io.PrintWriter;
  import javax.servlet.RequestDispatcher;
  import javax.servlet.ServletException;
  import javax.servlet.annotation.WebServlet;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import javax.servlet.http.HttpSession;


    @WebServlet(urlPatterns = {"/LoginServlet"})
     public class LoginServlet extends HttpServlet {
        @Override
      protected void doPost(HttpServletRequest request, HttpServletResponse  response)
        throws ServletException  , IOException {
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();

    String n=request.getParameter("username");
    String p=request.getParameter("password");

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

    if(LoginDao.validate(n,p)){
        RequestDispatcher rd = request.getRequestDispatcher("/welcome.jsp");
        rd.forward(request,response);
    }
    else{
        out.print("<p style="color:red">Sorry username or password error</p>");
        RequestDispatcher rd=request.getRequestDispatcher("/index.html");
        rd.include(request,response);
    }

    out.close();
}
}

<%@ 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>Welcome <%=session.getAttribute("name")%></title>
     </head>
     <body>
     <h3>Welcome </h3>
        <h4>
          Hello,
    <%=session.getAttribute("name")%></h4>
 </body>
   </html>

enter code here
        <?xml version="1.0" encoding="UTF-8"?>
  <web-app
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee  http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          xmlns="http://java.sun.com/xml/ns/javaee"
 version="2.5">
 <welcome-file-list>
 <welcome-file>index.html</welcome-file>
   </welcome-file-list>
     <servlet>
    <servlet-name>loginDao</servlet-name>
    <servlet-class>/LoginDao</servlet-class>
    </servlet>

      <servlet-mapping>
    <servlet-name>loginServlet</servlet-name>
    <url-pattern>/loginServlet</url-pattern>
      </servlet-mapping>

    <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    </welcome-file-list>
      </web-app>