JDBC(链表存储数据)

• 使用类来建立数据库的数据模板，进而通过对象来存储数据库实例
• 使用链表来存储数据对象

详情见注释

主类

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class JDBCDemo3 {
    public static void main(String[] args) {

        String sql = null;
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;

        try {
            //注册驱动
            Class.forName("com.mysql.jdbc.Driver");
            //获取连接
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/db", "root", "root");
            //获取执行sql的对象
            statement = connection.createStatement();
            //为sql赋值
            sql = "SELECT * FROM STUDENT3";
            //执行sql，将结果保存在ResultSet类型的结果集里
            resultSet = statement.executeQuery(sql);
            //声明list引用，接受student3Findall类型的值
            List<student3Findall> list = null;
            //声明数据库中表对应的类在循环外部，使引用复用
            student3Findall student3Findalls = null;
            //为list引用创建对象
            list = new ArrayList<student3Findall>();
            //循环遍历结果集
            while (resultSet.next()) {
                //创建  student3Findall 类型的对象，并为其赋值
                student3Findalls = new student3Findall();

                int id = resultSet.getInt(1);
                String name = resultSet.getString(2);
                int age = resultSet.getInt(3);
                String sex = resultSet.getString(4);
                String address = resultSet.getString(5);
                int math = resultSet.getInt(6);
                int english = resultSet.getInt(7);

                student3Findalls.setId(id);
                student3Findalls.setAge(age);
                student3Findalls.setSex(sex);
                student3Findalls.setEnglish(english);
                student3Findalls.setMath(math);
                student3Findalls.setName(name);
                student3Findalls.setAddress(address);

                //将对象装载进入列表
                list.add(student3Findalls);

            }

            System.out.println(list);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } finally {
            //释放资源
            //防止有空，造成资源未完全释放
            if (resultSet != null) {
                try {
                    resultSet.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (statement != null) {
                try {
                    statement.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (connection != null) {
                try {
                    connection.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
        }
    }
}

数据库数据格式类

import java.sql.ResultSet;
import java.util.List;

public class student3Findall {
    private int id;
    private String name;
    private String sex;
    private int age;
    private String address;
    private int math;
    private int english;

    public int getId() {
        return id;
    }

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

    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 int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public int getMath() {
        return math;
    }

    public void setMath(int math) {
        this.math = math;
    }

    public int getEnglish() {
        return english;
    }

    public void setEnglish(int english) {
        this.english = english;
    }

    @Override
    public String toString() {
        return "student3Findall{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", sex='" + sex + '\'' +
                ", age=" + age +
                ", address='" + address + '\'' +
                ", math=" + math +
                ", english=" + english +
                '}';
    }
}