unameservlet.java

JBuilder 2006 +SQL Server2000 +JavaBean+JSP开发的宠物医院管理系统

package com.pet.user.action;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import com.pet.user.model.DAO.UserDao;
import com.pet.user.model.DAO.impl.Userimpl;

public class UnameServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GB2312";

    //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 aa = request.getParameter("aa");
        UserDao userdao = new Userimpl();
        if (aa.equals("pt")) {
            String uname = request.getParameter("uname");
            if (userdao.cusname("select uname from users where uname='" + uname +"'") && userdao.cusname("select vname from vets where vname='" +uname + "'")) {
                out.println("<script type=\"text/javascript\" language=\"javascript\">alert(\"用户名已存在！\");window.history.go(-1);</script>");
            } else {
                out.println("<script type=\"text/javascript\" language=\"javascript\">alert(\"该用户名可以使用！\");window.history.go(-1);</script>");
            }
        }else{
            String vname = request.getParameter("vname");
            if (userdao.cusname("select uname from users where uname='" + vname +"'") && userdao.cusname("select vname from vets where vname='" +vname + "'")) {
                out.println("<script type=\"text/javascript\" language=\"javascript\">alert(\"用户名已存在！\");window.history.go(-1);</script>");
            } else {
                out.println("<script type=\"text/javascript\" language=\"javascript\">alert(\"该用户名可以使用！\");window.history.go(-1);</script>");
            }

        }
     out.close();
    }

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

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