package com.bjpowernode.javaweb.servlet;
import com.bjpowernode.javaweb.utils.DButil;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
@WebServlet(name = "register", value = "/register")
public class Register extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request,response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String Myname = request.getParameter("registerName");
        String Mypassword =request.getParameter("registerPwd");
        response.setContentType("text/html");
        response.setCharacterEncoding("GBK");
        Connection conn = null;
        PreparedStatement stmt = null;
        try {
            //注冊(cè)驅(qū)動(dòng)(作用:告訴Java程序，即將要連接的哪個(gè)品牌的數(shù)據(jù)庫(kù)）
            Class.forName("com.mysql.jdbc.Driver");
            //獲取連接（表示JVM的進(jìn)程和數(shù)據(jù)庫(kù)進(jìn)程之間的通道打開(kāi)了，這屬于進(jìn)程之間的通信，重量級(jí)的，使用完之后一定要關(guān)閉）
            String url = "jdbc:mysql://127.0.0.1:3306/book";
            String user = "root";
            String password = "123456";
            conn = DriverManager.getConnection(url,user,password);
            //獲取數(shù)據(jù)庫(kù)操作對(duì)象(專門（Statement專門執(zhí)行sql語(yǔ)句的）
            stmt = conn.prepareStatement("INSERT INTO user VALUES (?,?)");
            stmt.setString(1,Myname);
            stmt.setString(2,Mypassword);
            int count = stmt.executeUpdate();
            if(count==1){
                PrintWriter out = response.getWriter();
                out.println("<script>");
                out.println("alert('Registered successfully');");
                out.println("location.href='index.html'");//跳轉(zhuǎn)到用戶列表頁(yè)面
                out.println("</script>");
            }else{
                response.getWriter().print("注冊(cè)失敗");
            }
//            System.out.println(count == 1 ? "保存成功" : "保存失敗");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            DButil.close(conn,stmt,null);
        }
    }
}

package com.bjpowernode.javaweb.servlet;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Map;
@WebServlet(name = "Login", value = "/Login")
public class Login extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        String username = request.getParameter("userName");
        String password = request.getParameter("userPwd");
        Map<String,String> map = Mysql.user();
        response.setContentType("text/html");
        response.setCharacterEncoding("GBK");
        if(map.containsKey(username)) {
            System.out.println("進(jìn)入if判斷循環(huán)了");  //TODO  進(jìn)入循環(huán)了
            String PWD = map.get(username);
            System.out.println(PWD);//TODO   有值
            if (PWD.equals("admin")) {
                if (password.equals("admin")){
                    out.println("<script>");
                    out.println("alert('Log in successfully');");
                    out.println("location.href='Take_01'");//跳轉(zhuǎn)到管理員列表頁(yè)面
                    out.println("</script>");
                }
                else{
                    out.println("<script>");
                    out.println("alert('Dear, the account password is incorrect, please input it again');");
                    out.println("location.href='index.html'");//跳轉(zhuǎn)到用戶列表頁(yè)面
                    out.println("</script>");
                }
            }
            else if(PWD.equals(password)){
                out.println("<script>");
                out.println("alert('Log in successfully');");
                out.println("location.href='Take_02'");//跳轉(zhuǎn)到用戶列表頁(yè)面
                out.println("</script>");
            }
            else{
                out.println("<script>");
                out.println("alert('Dear, the account password is incorrect, please input it again');");
                out.println("location.href='index.html'");//跳轉(zhuǎn)到用戶列表頁(yè)面
                out.println("</script>");
//                System.out.println("美猴王");
//                response.getWriter().println("齊天大圣");
            }
        }
        else{
            out.println("<script>");
            out.println("alert('This account is not registered, dear, please register first?。?！');");
            out.println("location.href='index.html'");//跳轉(zhuǎn)到用戶列表頁(yè)面
            out.println("</script>");
        }
    }
}

package com.bjpowernode.javaweb.servlet;
import com.bipowernode.pojo.Olypic;
import com.bjpowernode.javaweb.utils.DButil;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
@WebServlet(name = "select",value = "/select")
public class Select extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        request.setCharacterEncoding("UTF-8");
        String name = request.getParameter("select_name");
        System.out.println(name);
        //連接數(shù)據(jù)庫(kù)
        Connection conn = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        List<Olypic> olypicList=new ArrayList<>();
        try {
            Class.forName("com.mysql.jdbc.Driver");
            //獲取連接
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mofa", "root", "123456");
            String sql = "select * from medals_table where Country=?";
            //編譯sql語(yǔ)句
            ps = conn.prepareStatement(sql);
            //賦值    第一個(gè)問(wèn)好賦值 country   國(guó)家名稱
            ps.setString(1, name);
            //查詢返回結(jié)果集    這個(gè)結(jié)果集只有一條記錄  ，國(guó)家名稱是主鍵  ，  故只有一條數(shù)據(jù)
            rs = ps.executeQuery();
            if (rs.next()) {
                String country = rs.getString("Country");
                String Glod = rs.getString("Glod_num");
                String Silver = rs.getString("Silver_num");
                String Copper = rs.getString("Copper_num");
                String id=rs.getString("id");
                String logo=rs.getString("logo");
                System.out.println("這是數(shù)據(jù)");
                System.out.println(country);
                System.out.println("Glod");
//                   String Sum=rs.getString("Sum");
                int G = Integer.valueOf(Glod).intValue();
                int S = Integer.valueOf(Silver).intValue();
                int C = Integer.valueOf(Copper).intValue();
                int A=G+S+C;
                String Sum=String.valueOf(A);
                //將數(shù)據(jù)封裝程Java對(duì)象
                Olypic olpic=new Olypic();
                olpic.setCountry(country);
                olpic.setGlod_num(Glod);
                olpic.setSilver_num(Silver);
                olpic.setCopper_num(Copper);
                olpic.setId(id);
                olpic.setSum(Sum);
                olpic.setLogo(logo);
                // TODO 將數(shù)據(jù)放入上面定義好的容器
                olypicList.add(olpic);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } finally {
            DButil.close(conn, ps, rs);
        }
        request.setAttribute("olypicList",olypicList);
        request.getRequestDispatcher("./take_03.jsp").forward(request,response);
    }
}