Ou est l'erreur dans ma servlet?

voilà j'ai l'erreur
Etat HTTP 405 - La méthode HTTP GET n''est pas supportée par cette URL

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type Rapport d''état

message La méthode HTTP GET n''est pas supportée par cette URL

description La méthode HTTP spécifiée n''est pas autorisée pour la ressource demandée.


ma servlet est :

import javax.servlet.http.HttpServlet;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.sql.*;
import java.sql.*;

public class login extends HttpServlet{ 
 
 public void doService(HttpServletRequest request, HttpServletResponse response)
   throws ServletException,IOException{
     
  response.setContentType("text/html");
  PrintWriter out = response.getWriter();
System.out.println("MySQL Connect Example.");

 Connection conn = null;
  String url = "jdbc:odbc:user_register";
  
  String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
  
 String username="";
 String userpass="";
 String strQuery= ""; 
  Statement st=null;
  ResultSet rs=null;
  HttpSession session = request.getSession(true);
  try {
  Class.forName(driver).newInstance();
  conn = DriverManager.getConnection(url,"","");
  if(request.getParameter("username")!=null &&
     request.getParameter("username")!="" && request.getParameter("password")!=null &&
     request.getParameter("password")!="")
  {
  username = request.getParameter("username").toString();
  userpass = request.getParameter("password").toString();
  strQuery ="select * from userregister where username ='"+username+"' and  password='"+userpass+"'";
 System.out.println(strQuery);
  st = conn.createStatement();
  rs = st.executeQuery(strQuery);
  int count=0;
  while(rs.next())
  {
  session.setAttribute("username",rs.getString(2));
  count++;
  }
  if(count>0)
  {
  response.sendRedirect("welcome.jsp");
  }
  else
  {
 response.sendRedirect("login.jsp");
  }
  }
  else
  {
 response.sendRedirect("login.jsp");
  }
  System.out.println("Connected to the database"); 
  conn.close();
  System.out.println("Disconnected from database");
  } catch (Exception e) {
  e.printStackTrace();
  }
  
 }
}

et sn web xml :

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="[http://www.w3.org/2001/XMLSchema-instance]" xmlns="[http://java.sun.com/xml/ns/javaee]" xmlns:web="[http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd]" xsi:schemaLocation="[http://java.sun.com/xml/ns/javaee] [http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd]" id="WebApp_ID" version="3.0">

<servlet>
<servlet-name>login</servlet-name>
<servlet-class>login</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>login</servlet-name>
<url-pattern>/toto</url-pattern>
</servlet-mapping>
</web-app>