一、准备工作
1.maven依赖
<dependencies>
<!-- mysql驱动 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.18</version>
</dependency>
<!-- junit测试 -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<!-- mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.4</version>
</dependency>
<!-- 日志相关依赖 -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.10</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.2</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.1.2</version>
</dependency>
</dependencies>
2.实体类
public class Person {
private Integer id;
private String name;
private String sex;
private String telephone;
private String address;
private Integer age;
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 String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getTelephone() {
return telephone;
}
public void setTelephone(String telephone) {
this.telephone = telephone;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "Person{" +
"id=" + id +
", name='" + name + '\'' +
", sex='" + sex + '\'' +
", telephone='" + telephone + '\'' +
", address='" + address + '\'' +
", age=" + age +
'}';
}
}
3.SQL资源
DROP TABLE IF EXISTS `person`;
CREATE TABLE `person` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`name` varchar(30) NOT NULL COMMENT '名字',
`sex` char(1) NOT NULL DEFAULT '男' COMMENT '性别',
`telephone` varchar(11) DEFAULT NULL COMMENT '手机号',
`address` varchar(50) DEFAULT NULL COMMENT '地址',
`age` tinyint(4) DEFAULT NULL COMMENT '年龄',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1295453 DEFAULT CHARSET=utf8;
INSERT INTO `person` VALUES ('1', 'xy', '男', '123456', '测试', '18');
INSERT INTO `person` VALUES ('2', 'ceshi', '女', '123456789', '美国', '20');
INSERT INTO `person` VALUES ('3', 'ceshi', '女', '123456789', '美国', '21');
二、Mybatis使用步骤
1.创建配置文件mybatis-config.xml
<?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>
<settings>
<!-- 使用指定日志实现类 -->
<setting name="lazyLoadTriggerMethods" value=""/>
<setting name="logImpl" value="SLF4J"/>
</settings>
<!--环境配置,连接的数据库,这里使用的是MySQL-->
<environments default="mysql">
<environment id="mysql">
<!--指定事务管理的类型,这里简单使用Java的JDBC的提交和回滚设置-->
<transactionManager type="JDBC"></transactionManager>
<!--dataSource 指连接源配置,type属性指使用的数据源工厂实现类,此处使用Mybatis提供的连接池-->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.cj.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/mybatis_study?serverTimezone=GMT%2B8"></property>
<property name="username" value="root"></property>
<property name="password" value="123456"></property>
</dataSource>
</environment>
</environments>
<!-- 映射mapper文件的路径-->
<mappers>
<mapper resource="mappers/PersonMapper.xml"></mapper>
</mappers>
</configuration>
2.创建mapper接口
public interface PersonMapper {
Person selectById(Integer id);
}
3.创建mapper.xml文件
<?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="com.my.mapper.PersonMapper">
<select id="selectById" parameterType="int" resultType="com.my.entity.Person">
select * from person where id = #{id}
</select>
</mapper>
4.创建测试类
public class MybatisTest {
private SqlSessionFactory sqlSessionFactory;
@Before
public void init() throws IOException {
String resource = "mybatis-config.xml";
//1.使用mybatis的工具读取配置文件
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
//2.创建sqlSessionFactory
sqlSessionFactory = sqlSessionFactoryBuilder.build(inputStream);
inputStream.close();
}
@Test
public void test() {
//3.获取sqlSession
SqlSession sqlSession = sqlSessionFactory.openSession();
//4.获取mapper接口实现类
PersonMapper personMapper = sqlSession.getMapper(PersonMapper.class);
//5.调用方法
Person person = personMapper.selectById(1);
System.out.println(person);
//6.释放资源
sqlSession.close();
}
}
5.目录结构