userlogin.java

网上书店网站源代码

package bookshop.bean;
import java.io.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import bookshop.bean.*;
public class UserLogin extends HttpServlet{
	public void doGet(HttpServletRequest request,
	HttpServletResponse response)
	 throws ServletException, IOException {
		HttpSession session=request.getSession();
		String toJSP="/main.jsp";
		if(session.getAttribute("username")==null){
			String name=request.getParameter("name");
			String pass=request.getParameter("pass");
			String sql="select * from b_user where b_name='"+name+"' and b_pass='"+pass+"'";
			DataBase db=new DataBase();
			ResultSet rs=db.executeQuery(sql);
			try{
				if(rs.next()){
					session.setAttribute("username",name);
					toJSP="/main.jsp/";
				}else
				{
					toJSP="/login.jsp/";
					request.setAttribute("errinf","bu");
				}
			}catch(Exception e){
				System.out.println(e.getMessage());
			}
			db.closeConnection();
		}
		RequestDispatcher dispatcher=request.getRequestDispatcher(toJSP);
		dispatcher.forward(request,response);
	}
	public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
	{
		doGet(request,response);
	}
}