2024.3.13

第七天

所花时间：2小时

代码量：400+

博客量：1

了解到的知识点：今天把开学考试的测试代码重新看了一下，首先是连接数据库的代码和bean文件部分，明天更新计划申请的dao层和servlet

package db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DB {
    public static String db_url = "jdbc:mysql://localhost:3306/tb_user?useSSL=false&serverTimezone=UTC&characterEncoding=UTF-8&useOldAliasMetadataBehavior=true";
    public static String db_user = "root";
    public static String db_pass = "ADGJL12345syl";

    public static Connection getConn () {
        Connection conn = null;

        try {
            Class.forName("com.mysql.cj.jdbc.Driver");//加载驱动
            conn = DriverManager.getConnection(db_url, db_user, db_pass);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return conn;
    }

    /**
     * 关闭连接
     * @param state
     * @param conn
     */
    public static void close (Statement state, Connection conn) {
        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    public static void close (ResultSet rs, Statement state, Connection conn) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if (state != null) {
            try {
                state.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) throws SQLException {
        Connection conn = getConn();
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        String sql ="select * from tb_user.tiaoji";
        pstmt = conn.prepareStatement(sql);
        rs = pstmt.executeQuery();
        if(rs.next()){
            System.out.println("空");
        }else{
            System.out.println("不空");
        }
        sql ="select * from tb_user.jihua";
        pstmt = conn.prepareStatement(sql);
        rs = pstmt.executeQuery();
        if(rs.next()){
            System.out.println("空");
        }else{
            System.out.println("不空");
        }
    }
}

package bean;

public class Jihua {
    private String zhuanye;
    private int number;
    private int zongfen;
    private int zhengzhi;
    private int yingyu;
    private int shuxue;
    private String time;

    public Jihua(String zhuanye, int number, int zongfen, int zhengzhi, int yingyu, int shuxue, String time) {
        this.zhuanye = zhuanye;
        this.number = number;
        this.zongfen = zongfen;
        this.zhengzhi = zhengzhi;
        this.yingyu = yingyu;
        this.shuxue = shuxue;
        this.time = time;
    }

    public Jihua() {
    }

    public String getZhuanye() {
        return zhuanye;
    }

    public void setZhuanye(String zhuanye) {
        this.zhuanye = zhuanye;
    }

    public int getNumber() {
        return number;
    }

    public void setNumber(int number) {
        this.number = number;
    }

    public int getZongfen() {
        return zongfen;
    }

    public void setZongfen(int zongfen) {
        this.zongfen = zongfen;
    }

    public int getZhengzhi() {
        return zhengzhi;
    }

    public void setZhengzhi(int zhengzhi) {
        this.zhengzhi = zhengzhi;
    }

    public int getYingyu() {
        return yingyu;
    }

    public void setYingyu(int yingyu) {
        this.yingyu = yingyu;
    }

    public int getShuxue() {
        return shuxue;
    }

    public void setShuxue(int shuxue) {
        this.shuxue = shuxue;
    }

    public String getTime() {
        return time;
    }

    public void setTime(String time) {
        this.time = time;
    }
}

package bean;

public class login {
    public char id;
    public char password;

    public login(char id, char password) {
        this.id = id;
        this.password = password;
    }

    public login() {
    }

    public char getId() {
        return id;
    }

    public void setId(char id) {
        this.id = id;
    }

    public char getPassword() {
        return password;
    }

    public void setPassword(char password) {
        this.password = password;
    }
}

package bean;

public class Tiaoji {
    private String name;
    private String id;
    private String zhuanye;
    private String zongfen;
    private String sizhang;
    private String yingyu;
    private String shuxue;
    private String zonghe;
    private String jieguo;

    public Tiaoji(String name, String id, String zhuanye, String zongfen, String sizhang, String yingyu, String shuxue, String zonghe, String jieguo) {
        this.name = name;
        this.id = id;
        this.zhuanye = zhuanye;
        this.zongfen = zongfen;
        this.sizhang = sizhang;
        this.yingyu = yingyu;
        this.shuxue = shuxue;
        this.zonghe = zonghe;
        this.jieguo = jieguo;
    }

    public Tiaoji() {
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getZhuanye() {
        return zhuanye;
    }

    public void setZhuanye(String zhuanye) {
        this.zhuanye = zhuanye;
    }

    public String getZongfen() {
        return zongfen;
    }

    public void setZongfen(String zongfen) {
        this.zongfen = zongfen;
    }

    public String getSizhang() {
        return sizhang;
    }

    public void setSizhang(String sizhang) {
        this.sizhang = sizhang;
    }

    public String getYingyu() {
        return yingyu;
    }

    public void setYingyu(String yingyu) {
        this.yingyu = yingyu;
    }

    public String getShuxue() {
        return shuxue;
    }

    public void setShuxue(String shuxue) {
        this.shuxue = shuxue;
    }

    public String getZonghe() {
        return zonghe;
    }

    public void setZonghe(String zonghe) {
        this.zonghe = zonghe;
    }

    public String getJieguo() {
        return jieguo;
    }

    public void setJieguo(String jieguo) {
        this.jieguo = jieguo;
    }
}