世界疫情可视化开发（四）

今天把剩余的所有的全部开发完了

　dao层：访问数据库

package Dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import DBUtil.Util;
import bin.Country;
import bin.Info;
public class Dao {
    
    public List<Country> getAllCountry() {
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        List<Country> countryList = new ArrayList<>();
        try {
            con = Util.getConnection();
            String sql = "select * from yiqing_world order by confirmed_num DESC";
            ps = con.prepareStatement(sql);
            rs = ps.executeQuery();
            while(rs.next()) {   
                Country country = new Country();
                country.setId(rs.getString(1));
                country.setName(rs.getString(2));
                country.setConfirmed_num(rs.getString(3));
                country.setYisi_num(rs.getString(6));
                country.setCured_num(rs.getString(4));
                country.setDead_num(rs.getString(5));
                country.setDate(rs.getString(7));
                countryList.add(country);
            }
            return countryList;
        }catch(Exception e) {
            throw new RuntimeException(e);
        }finally {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            Util.release(con, ps);
        }
    }

    public List<Country> getAllChinaConfirmed() {
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        List<Country> countryList = new ArrayList<>();
        try {
            con = Util.getConnection();
            String sql = "select * from world_";
            ps = con.prepareStatement(sql);
            rs = ps.executeQuery();
            while(rs.next()) {   
                Country country = new Country();
                country.setName(rs.getString(1));
                country.setConfirmed_num(rs.getString(2));
                country.setYisi_num(rs.getString(3));
                country.setCured_num(rs.getString(4));
                country.setDead_num(rs.getString(5));
                country.setDate(rs.getString(7));
                countryList.add(country);
            }
            return countryList;
        }catch(Exception e) {
            throw new RuntimeException(e);
        }finally {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            Util.release(con, ps);
        }
    }
    // 查询全世界所有的确诊人数
    public int countryConfirmedCount() {
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        try {
            con = Util.getConnection();
            String sql = "select sum(confirmed_num) as count from yiqing_world";
            ps = con.prepareStatement(sql);
            rs = ps.executeQuery();
            return rs.getInt("count");
        }catch(Exception e) {
            throw new RuntimeException(e);
        }finally {          
            Util.release(con, ps);
        }
    }
}

　　

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　　Servlet：

　　获取世界所有的数据

package Servlet;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

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 javax.servlet.http.HttpSession;

import org.apache.catalina.Session;

import com.google.gson.Gson;

import Dao.Dao;
import bin.Country;

/**
 * Servlet implementation class GetAllWorldConfirmedServlet
 */
@WebServlet("/GetAllWorldConfirmedServlet")
public class GetAllWorldConfirmedServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    Dao dao = new Dao();
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public GetAllWorldConfirmedServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        request.setCharacterEncoding("UTF-8");
        List<Country> countryList = dao.getAllCountry();
        int countryConfirmedCount=0,countryCuredCount=0,countryDeadCount=0;
        for(int i=0;i<countryList.size();i++) {
            countryConfirmedCount += Integer.valueOf(countryList.get(i).getConfirmed_num());
            countryCuredCount += Integer.valueOf(countryList.get(i).getCured_num());
            countryDeadCount += Integer.valueOf(countryList.get(i).getDead_num());
        }
        HttpSession session = request.getSession();
        session.setAttribute("countryList",countryList);
        session.setAttribute("countryConfirmedCount",countryConfirmedCount);
        session.setAttribute("countryCuredCount",countryCuredCount);
        session.setAttribute("countryDeadCount",countryDeadCount);
        session.setAttribute("lastUpdateTime",countryList.get(3).getDate());
        Gson gson = new Gson();        
        String json = gson.toJson(countryList);
        response.getWriter().write(json);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

　　获取中国历史所有的数据：（本来应该是全世界的，但是我爬下来的数据没对全世界的历史数据，只有更新数据）

　　

package Servlet;

import java.io.IOException;
import java.util.List;

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 com.google.gson.Gson;

import Dao.Dao;
import bin.Country;

/**
 * Servlet implementation class GetAllChinaConfirmedServlet
 */
@WebServlet("/GetAllChinaConfirmedServlet")
public class GetAllChinaConfirmedServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    Dao dao = new Dao();
    /**
     * @see HttpServlet#HttpServlet()
     */
    public GetAllChinaConfirmedServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        request.setCharacterEncoding("UTF-8");
        List<Country> ChinaList = dao.getAllChinaConfirmed();
        Gson gson = new Gson();        
        String json = gson.toJson(ChinaList);
        response.getWriter().write(json);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

　　

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　　连接数据的就不发了。

　 结尾：做的过程没有遇到太多的问题。遇到的问题自己最后都解决了。之前做echarts的测试感觉很难毫无头绪，耗费时间长。现在还是比较上手。人都是会进步，只有学了就有效果。如果读者知道哪个网址有世界历史数据，可以给我留言一下谢谢。任何对于代码有问题的、不懂得，留言。大佬还需要多给我提意见。