ubuntu20.04中mybatis连接mysql

可以使用以下步骤配置：
1. 安装MySQL和MyBatis

sudo apt install mysql-server mysql-client
sudo apt install libmysql-java
sudo apt install maven

2. 创建数据库和表

mysql -u root -p
CREATE DATABASE testdb;
USE testdb;
CREATE TABLE user (
    id INT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(20) NOT NULL,
    age INT NOT NULL,
    email VARCHAR(50) NOT NULL
)

3. 配置MyBatis
在mybatis-config.xml中添加以下内容：

<configuration>
  <environments default="development">
    <environment id="development">
      <transactionManager type="JDBC" />
      <dataSource type="POOLED">
        <property name="driver" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost:3306/testdb?useSSL=false&amp;serverTimezone=UTC" />
        <property name="username" value="root" />
        <property name="password" value="yourpassword" />
      </dataSource>
    </environment>
  </environments>
  <mappers>
    <mapper resource="mapper/UserMapper.xml" />
  </mappers>
</configuration>

4. 编写Mapper接口和SQL语句
创建UserMapper.xml文件，添加以下内容:

<mapper namespace="com.example.mapper.UserMapper">
  <select id="selectAllUsers" resultType="User">
    SELECT * FROM user
  </select>
</mapper>

创建User.java类和UserMapper.java接口

public class User {
  private int id;
  private String name;
  private int age;
  private String email;
  // getters and setters
}

public interface UserMapper {
  List<User> selectAllUsers();
}

5. 测试MyBatis连接MySQL
在代码中使用UserMapper接口中的方法查询数据

public static void main(String[] args) {
    SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("mybatis-config.xml"));
    try(SqlSession session = sessionFactory.openSession()) {
      UserMapper userMapper = session.getMapper(UserMapper.class);
      List<User> users = userMapper.selectAllUsers();
      for(User user : users) {
        System.out.println(user.getName());
      }
    }
}