1.创建一个数据库一会用来连接

2.使用idea新建一个Java项目

3.在pom文件中加上相关依赖，并配置Maven路径

<dependencies><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.29</version></dependency>
</dependencies>

新建jdbcdemo包和其中的类

package com.qcby.jdbcdemo;import com.mysql.jdbc.Driver;import java.sql.*;public class JdbcDemo {//主方法 主函数 程序入口public static void main(String[] args) {ResultSet resultSet = null;Statement statement = null;Connection connection = null;try {//1,加载驱动    2种  反射加载    直接加载//Class.forName("com.mysql.jdbc.Driver");DriverManager.registerDriver(new Driver());//2,获取连接    4个  用户名 密码  url//jdbc:mysql://localhost:3306/test  主协议 二层协议    mysql   IP地址    端口号     127.0.0.1:3306connection = DriverManager.getConnection("jdbc:mysql:///jdbctest","root","123456");//3,编写sqlString sql = "select * from student";//4,获取执行sql的对象  2种  不安全 sql注入问题 preparedStatementstatement = connection.createStatement();//5,执行sql   拿到结果集resultSet = statement.executeQuery(sql);//6,遍历结果集while (resultSet.next()){Student student = new Student();student.setId(resultSet.getInt("id"));student.setName(resultSet.getString("name"));student.setAge(resultSet.getInt("age"));student.setSex(resultSet.getString("sex"));System.out.println(student);}}catch (Exception e) {throw new RuntimeException(e);}finally {//永远执行//7，关闭资源try {resultSet.close();statement.close();connection.close();} catch (Exception e) {throw new RuntimeException(e);}}}
}

package com.qcby.jdbcdemo;public class Student {private Integer id;private String name;private Integer age;private String sex;public Student() {}public Student(Integer id, String name, Integer age, String sex) {this.id = id;this.name = name;this.age = age;this.sex = sex;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getSex() {return sex;}public void setSex(String sex) {this.sex = sex;}@Overridepublic String toString() {return "Student{" +"id=" + id +", name='" + name + '\'' +", age=" + age +", sex='" + sex + '\'' +'}';}
}

然后运行，就可以从数据库中读取数据了