我创建了一个简单的web应用程序。我需要检查一下,当有人预订房间时,到达日期是否不同。例如:人员a:在数据中预订房间:2018年7月12日人员b:在数据中预订房间:2018年7月12日(他不能,因为还有人员a)。
我有这个数据库:
酒店预订
cid,cname,email,到达日期,离开日期,人,房间,键入房间,评论,状态,uid。
这是我的密码
酒店预订.java
package hotel;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
*
* @author OOPs
*/
public class Hotelbooking extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String s1 = request.getParameter("id");
String s2 = request.getParameter("name");
String s3 = request.getParameter("email");
String s4 = request.getParameter("arrivaldate");
String s5 = request.getParameter("departuredate");
String s6 = request.getParameter("person");
String s7 = request.getParameter("rooms");
String s8 = request.getParameter("type_room");
String s9 = request.getParameter("comment");
String s10 = request.getParameter("status");
// sesson..........
HttpSession session=request.getSession(true);
String s11 = (String)session.getAttribute("sessname");
out.println(s11);
try {
Class.forName("com.mysql.jdbc.Driver");
// out.println("driver loaded");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/HotelReservation","root" ,"123456789");
// out.println("Connect");
Statement st = con.createStatement();
// out.println("conncetion successfull");
int rs = st.executeUpdate("insert into hotel_booking (cname,email,arrival_date,departure_date,person,room,type_room,comment,status,uid)values ('"+s2+"','"+s3+"','"+s4+"','"+s5+"','"+s6+"','"+s7+"','"+s8+"','"+s9+"','"+s10+"','"+s11+"')");
// out.println(s1);
// out.println(s2);
out.println("<h1> Register sucsefulltttt </h1>");
/* if(rs == 1)
{
out.println("<script type=\"text/javascript\">");
out.println("alert('send successfully');");
out.println("</script>");
//response.sendRedirect("home.jsp");
}else{
}*/
response.sendRedirect("thankyoureg.jsp");
}catch(Exception e){
out.println("nahiiiiiiiiiiiii" +e);
}
finally {
out.close();
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
你认为我该怎么办??谢谢你的帮助。
1条答案
按热度按时间aiazj4mn1#
检查如下查询是否返回
0
.如果它回来了
0
客人要入住的当天房间没有人。否则就是。替代品
$1
客人希望到达的当天$2
房间(号码、名字或你用的任何东西)。我假设签入/ checkout 时间的处理方式如下:
在某一天的晚上办理入住手续。
在某一天的早晨退房。也就是说,一位客人可以在另一位客人退房的当天办理入住手续。
如果这个假设是错误的,那么就必须相应地调整比较运算符。
还可以考虑使用参数化查询,而不是使用未初始化的用户输入值进行字符串连接。后者是危险的,您的应用程序容易受到sql注入攻击。另外,参数化查询有助于为给定的数据类型找到正确的表示形式,从而防止由于错误表示值而导致的错误。