import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import com.bwm.db.*;
import java.sql.*;
import com.bwm.login.*;
public class log extends HttpServlet{
    private static final String CONTENT_TYPE="text/html;charset=GBK";
    public void init() throws ServletException{
    }
 public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{
    request.setCharacterEncoding("GBK");
    response.setContentType(CONTENT_TYPE);
    HttpSession session=request.getSession();
    ServletContext application=this.getServletContext();
    if(session.getAttribute("username")!=null){
        response.sendRedirect("index1.jsp");
        return;
    }
    String username=request.getParameter("username");
   if()
 }
    
}