用Java实现增删改查

迈不过友情╰ 2022-01-29 02:07 339阅读 0赞

1.先写一个student类：

public class student {
        private String name;
        private String sex;
        private String brithday;
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getSex() {
            return sex;
        }
    
        public void setSex(String sex) {
            this.sex = sex;
        }
    
        public student() {
        }
    
        public student(String name, String sex, String brithday) {
            this.name = name;
            this.sex = sex;
            this.brithday = brithday;
        }
    
        public String getBrithday() {
            return brithday;
        }
    
        public void setBrithday(String brithday) {
            this.brithday = brithday;
        }
    
        @Override
        public String toString() {
            return "student{" +
                    "name='" + name + '\'' +
                    ", sex='" + sex + '\'' +
                    ", brithday='" + brithday + '\'' +
                    '}';
        }
    }

2.写一个可以获取文件上的资源并注册驱动的类（文件自己按照自己的数据库填）

public class Deu_tils {
        private static String diverClass;   //注册驱动的jar包地址值
        private static String url;  //数据库的表格地址值
        private static String user; //Mysql的用户名
        private static String password; //Mysql的用户密码
    
        static {
            ResourceBundle rb=ResourceBundle.getBundle("dbinfo");   //获取文件的资源
            diverClass=rb.getString("driverClass");
            url=rb.getString("url");
            user=rb.getString("user");
            password=rb.getString("password");
            try {
                Class.forName(diverClass);  //注册驱动
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 得到资源的方法
         * @return 资源
         * @throws SQLException
         */
        public static Connection getConnection() throws SQLException {
            return DriverManager.getConnection(url,user,password);
        }
    }

*  3.实现增删改查
    
        public class DoLogin {
            private String sql;
            private PreparedStatement pstmt;
            private Connection conn;
        
            /**
             * 增加数据库里面一条学生对象信息的方法
             *
             * @param s
             * @return
             */
            public void Insert(student s) throws SQLException {
                Connection conn = Deu_tils.getConnection();
                int i = 0;
                sql = "INSERT INTO `text2`.`student`(`name`, `sex`, `brithday`) VALUES (?,?,?)";
                    pstmt =conn.prepareStatement(sql);
                    pstmt.setString(1, s.getName());
                    pstmt.setString(2, s.getSex());
                    pstmt.setString(3, s.getBrithday());
                    i = pstmt.executeUpdate();
                    pstmt.close();
                    conn.close();
            }
        
            /**
             *
             * 根据数据库id改名字性别和生日的方法
             * @param s
             * @return
             * @throws SQLException
             */
            public void Update(int id,student s) throws SQLException {
                Connection conn = Deu_tils.getConnection();
                int i = 0;
                sql ="UPDATE `text2`.`student` SET `name` = '"+s.getName()+"', `sex` = '"+s.getSex()+"', `brithday` = '"+s.getBrithday()+"' WHERE `id` = "+id;
                    pstmt =conn.prepareStatement(sql);
                    i = pstmt.executeUpdate();
                    pstmt.close();
                    conn.close();
            }
        
            /**
             * 根据对象名删除数据库对象信息的方法
             * @param name
             * @return
             * @throws SQLException
             */
            public void Delete(String name) throws SQLException {
                Connection conn = Deu_tils.getConnection();
                int i = 0;
                sql ="DELETE FROM `text2`.`student` WHERE `name` = '"+name+"'";
                    pstmt =conn.prepareStatement(sql);
                    i = pstmt.executeUpdate();
                    pstmt.close();
                    conn.close();
            }
        
            /**
             *  查询表格的方法
             * @throws SQLException
             */
            public void Select() throws SQLException {
                Connection conn = Deu_tils.getConnection();
                sql = "SELECT * FROM student;";
                pstmt = conn.prepareStatement(sql);
                ResultSet rs = pstmt.executeQuery();
                student s = new student();
                while (rs.next()) {
                    System.out.println(rs.getObject("id"));
                    System.out.println(rs.getObject("name"));
                    System.out.println(rs.getObject("sex"));
                    System.out.println(rs.getObject("brithday"));
                    System.out.println("---------------------------");
                }
                conn.close();
                pstmt.close();
                rs.close();
            }
        }

4.测试类：

public class Text {
        public static void main(String[] args) throws SQLException {
            Scanner sc=new Scanner(System.in);
            System.out.println("请输入录入对象的名字：");
            String names=sc.next();
            System.out.println("请输入录入对象的性别：");
            String sexs=sc.next();
            System.out.println("请输入录入对象的生日：");
            String bris=sc.next();
            student s1=new student(names,sexs,bris);
            DoLogin dl1=new DoLogin();
            dl1.Insert(s1);
            dl1.Select();
    
            System.out.println("请输入要改对象的id：");
            int id=sc.nextInt();
            System.out.println("请输入要改的数据值名字：");
            String name=sc.next();
            System.out.println("请输入要改的数据值性别：");
            String sex=sc.next();
            System.out.println("请输入要改的数据值生日：");
            String bri=sc.next();
            student s2=new student(name,sex,bri);
            DoLogin dl2=new DoLogin();
            dl2.Update(id,s2);
            dl2.Select();
    
            System.out.println("请输入您要删除的对象姓名：");
            String namess=sc.next();
            DoLogin dl3=new DoLogin();
            dl3.Delete(namess);
            dl3.Select();
        }
    }

<table style="width:500px;"> 
 <thead> 
  <tr> 
   <th>id</th> 
   <th>name</th> 
   <th>sex</th> 
   <th>brithday</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1</td> 
   <td>张三</td> 
   <td>男</td> 
   <td>1999-02-13</td> 
  </tr> 
  <tr> 
   <td>2</td> 
   <td>李四</td> 
   <td>男</td> 
   <td>1999-08-16</td> 
  </tr> 
  <tr> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
 </tbody> 
</table>

最后：能力有限，如有不对之处，还请指教。