MyBatis二、搭建 MyBatis

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.26</version>
</dependency>

<dataSource type="POOLED">
    <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
    <property name="url" value="jdbc:mysql://localhost:3306/mydatabase?useSSL=false&serverTimezone=UTC"/>
    <property name="username" value="root"/>
    <property name="password" value="password"/>
</dataSource>

<dependencies>
	<dependency>
		<groupId>org.mybatis</groupId>
		<artifactId>mybatis</artifactId>
		<version>3.5.7</version>
	</dependency>

	<dependency>
		<groupId>junit</groupId>
		<artifactId>junit</artifactId>
		<version>4.13</version>
		<scope>test</scope>
	</dependency>

	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>8.0.16</version>
	</dependency>
</dependencies>

create database `ssm` character set 'utf8mb4';

use `ssm`;

create table if not exists `t_user`(
    `id` int primary key auto_increment,
    `username` varchar(20),
    `password` varchar(20),
    `age` int,
    `gender` char,
    `email` varchar(50)
) character set 'utf8mb4';

package cn.keke.mybatis.pojo;

/**
 * Copyright (C) 2024 - 2024 keke， Inc. All Rights Reserved
 *
 * @Desc :
 * @Time : 2024/6/2 14:46
 * @Author : Code_By_keke
 * @Email : 2284037977@qq.com
 * @Class : User
 * @IDE : IntelliJ IDEA
 */
public class User {

	private Integer id;

	private String username;

	private String password;
	
	private Integer age;
	
	private String gender;
	
	private String email;
	
	public User(){
		
	}

	public User(Integer id, String username, String password, Integer age, String gender, String email) {
		this.id = id;
		this.username = username;
		this.password = password;
		this.age = age;
		this.gender = gender;
		this.email = email;
	}

	public Integer getId() {
		return id;
	}

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

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

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

	public Integer getAge() {
		return age;
	}

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

	public String getGender() {
		return gender;
	}

	public void setGender(String gender) {
		this.gender = gender;
	}

	public String getEmail() {
		return email;
	}

	public void setEmail(String email) {
		this.email = email;
	}

	@Override
	public String toString() {
		return "User{" +
				"id=" + id +
				", username='" + username + '\'' +
				", password='" + password + '\'' +
				", age=" + age +
				", gender='" + gender + '\'' +
				", email='" + email + '\'' +
				'}';
	}
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
   	PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
   	"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
   <!-- 设置连接数据库的环境 -->
   <environments default="development">
   	<environment id="development">
   		<transactionManager type="JDBC" />
   		<dataSource type="POOLED">
   			<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
   			<property name="url" value="jdbc:mysql://localhost:3306/ssm?serverTimezone=UTC"/>
   			<property name="username" value="root"/>
   			<property name="password" value="123456"/>
   		</dataSource>
   	</environment>
   </environments>
   
   <!-- 引入 MyBatis 的映射文件 -->
   <mappers>
   	<mapper resource=""/>
   </mappers>
</configuration>

package cn.keke.mybatis.mapper;

/**
 * Copyright (C) 2024 - 2024 keke， Inc. All Rights Reserved
 *
 * @Desc :
 * @Time : 2024/6/2 15:18
 * @Author : Code_By_keke
 * @Email : 2284037977@qq.com
 * @Class : UserMapper
 * @IDE : IntelliJ IDEA
 */
public interface UserMapper {
	
	int insertUser();
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
		PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
		"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.keke.mybatis.mapper.UserMapper">

	<!--
		mapper 接口和映射文件要保证两个一致：
			1.mapper 接口中的全类名和映射文件的 namespace 一致
			2.mapper 接口中的方法名要和映射文件中的 SQL 的 id 保持一致
	 -->

	<insert id="insertUser">
		insert into t_user (`id`, `username`, `password`, `age`, `gender`, `email`)
		values (null, 'admin', '123456', 23, '男', '12345@qq.com');
	</insert>
</mapper>

package cn.keke;

import cn.keke.mybatis.mapper.UserMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;

/**
 * Copyright (C) 2024 - 2024 keke， Inc. All Rights Reserved
 *
 * @Desc :
 * @Time : 2024/6/2 21:49
 * @Author : Code_By_keke
 * @Email : 2284037977@qq.com
 * @Class : MyBatisTest
 * @IDE : IntelliJ IDEA
 */
public class MyBatisTest {

	@Test
	public void testInsert() throws IOException {
		// 获取核心配置文件的输入流
		InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
		// 获取 SqlSessionFactoryBuilder 对象
		SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
		// 获取 SqlSessionFactory 对象
		SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(is);
		// 获取 SQL 的会话对象 SqlSession(会自动提交事务)，是 MyBatis 提供的操作数据库的对象
		SqlSession sqlSession = sqlSessionFactory.openSession(true);
		// 获取 UserMapper 的代理实现类对象
		UserMapper mapper = sqlSession.getMapper(UserMapper.class);
		// 调用 mapper 中的方法，实现添加用户信息的功能
		int result = mapper.insertUser();
		System.out.println("结果：" + result);
		// 提交事务
		sqlSession.commit();
		// 关闭 SqlSession
		sqlSession.close();
	}
}

<dependency>
	<groupId>log4j</groupId>
	<artifactId>log4j</artifactId>
	<version>1.2.17</version>
</dependency>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
	<appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
		<param name="Encoding" value="UTF-8"/>
		<layout class="org.apache.log4j.PatternLayout">
			<param name="ConversionParttern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m  (%F:%L) \n"/>
		</layout>
	</appender>
	<logger name="java.sql">
		<level value="debug"/>
	</logger>
	<logger name="org.apache.ibatis">
		<level value="info"/>
	</logger>
	<root>
		<level value="debug"/>
		<appender-ref ref="STDOUT"/>
	</root>
</log4j:configuration>