loginservlet.java~9~

jsp设计的留言板,供大家参考,使用的是文本文件作为数据库

package bookservlets;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import bookutil.DataDo;
public class LoginServlet extends HttpServlet {
  private static final String CONTENT_TYPE = "text/html; charset=Big5";

  //Initialize global variables
  public void init() throws ServletException {
  }

  //Process the HTTP Get request
  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType(CONTENT_TYPE);
    PrintWriter out = response.getWriter();
    String var0 = request.getParameter("master_name").trim();
    String var1 = request.getParameter("master_psw").trim();
    var0 = var0.replaceAll("'","''");
    if (var1 == null || var0 == null
        || var0.length() == 0 || var1.length() == 0)
    {
       out.println("<script>window.alert(\"Please Enter Your Login Name And Password !\");</script>");
       out.println("<script>window.location=\"manage/masterlogin.jsp\"</script>");
       return;
    }
    ArrayList alist = null;
    ArrayList inlist = null;
    DataDo db = new DataDo();
    alist = db.dataQuery("select * from masterlg where master_name='"+var0+"'",5,"1");
    System.out.println("---------------alist:"+alist.size());
    inlist = (ArrayList)alist.get(0);
    db.dataClose();
    if (inlist.get(db.getColumn("master_psw")).equals(var1))
    {
      Cookie ck = new Cookie("master",var0);
      response.addCookie(ck);
      response.sendRedirect("manage/manage.jsp");
      return;
    }
    else
    {
      out.println("<script>window.alert(\"Login Fail !\");</script>");
      out.println("<script>window.location=manage/masterlogin.jsp</script>");
      return;
    }
  }

  //Process the HTTP Post request
  public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doGet(request, response);
  }

  //Clean up resources
  public void destroy() {
  }
}