目录
一、创建数据库
CREATE DATABASE `mybatis_db` USE `mybatis_db` CREATE TABLE `user`( `id` int(20), `name` VARCHAR(30), `pwd` VARCHAR(30), PRIMARY KEY(`id`) )ENGINE=INNODB DEFAULT CHARSET=utf8; INSERT INTO `user` VALUES (1, 'hongyyds', '123123'), (2, 'shiyu', '110000'), (3, 'feiyu', '666321')
二、创建mybatis核心配置文件
2.1、在maven的资源目录（resource）中创建mybatis核心配置文件
<?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>
<environments default="development">
<!--id 标识-->
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<!--mysql驱动程序-->
<property name="driver" value="com.mysql.jdbc.Driver"/>
<!--数据库URL地址-->
<property name="url" value="jdbc:mysql://localhost:3306/mybatis_db?useSSl=true&useUnicode=true&characterEncoding=utf-8"/>
<!--mysql账号-->
<property name="username" value="root"/>
<!--mysql密码-->
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<!--每一个xml配置文件都需要在mybatis的核心配置文件中注册才能生效-->
<mappers>
<mapper resource="cong/hong/mapper/UserMapper.xml"/>
</mappers>
</configuration>
三、配置pom.xml
3.1、配置插件junit、mysql和mybatis
<dependencies>
<!-- mysql驱动 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.28</version>
</dependency>
<!-- mybatis驱动 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.9</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.13</version>
<scope>test</scope>
</dependency>
</dependencies>
3.2、配置文件目录过滤（解决maven项目文件不输出的情况）
<!--解决maven项目文件不输出的情况-->
<build>
<resources>
<resource>
<directory>src/main/java</directory>
<includes>
<include>**/*.xml</include>
<include>**/*.properties</include>
</includes>
</resource>
<resource>
<directory>src/main/resources</directory>
<includes>
<include>**/*.xml</include>
<include>**/*.properties</include>
</includes>
</resource>
</resources>
</build>
四、创建pojo
package cong.hong.pojo;
import java.io.Serializable;
public class User implements Serializable {
private String id;
private String name;
private String pwd;
@Override
public String toString() {
return "User{" +
"id='" + id + '\'' +
", name='" + name + '\'' +
", pwd='" + pwd + '\'' +
'}';
}
public User() {
}
public User(String id, String name, String pwd) {
this.id = id;
this.name = name;
this.pwd = pwd;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
}
五、创建工具类获取SqlSession对象
package cong.hong.utils;
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 java.io.IOException;
import java.io.InputStream;
public class MybatisUtils {
private static InputStream inputStream;
private static SqlSessionFactory sqlSessionFactory;
static {
try {
//mybatis核心配置文件路径
String resource = "config.xml";
//读取配置文件
inputStream = Resources.getResourceAsStream(resource);
//构建SqlSessionFactory类对象
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch (IOException e) {
e.printStackTrace();
}finally {
if(inputStream != null){
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
* @return SqlSession对象
*/
public static SqlSession getSqlSession(){
return sqlSessionFactory.openSession();
}
}
六、创建Dao层接口
package cong.hong.mapper;
import cong.hong.pojo.User;
import java.util.List;
public interface UserMapper {
//或如用戶列表
public List<User> getUserList();
}
七、创建Dao层所对应的xml文件
7.1、创建xml文件实现查询功能
<?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">
<!-- namespace 绑定的工作区 Java文件-->
<mapper namespace="cong.hong.mapper.UserMapper">
<!--select：查询， id：接口中的要实现的方法名， resultType：返回值的类型（泛型中的类型） -->
<select id="getUserList" resultType="cong.hong.pojo.User">
select * from mybatis_db.user
</select>
</mapper>
7.2、在MyBatis核心配置文件中注册xml文件
注：每一个Dao层接口对象对应的xml文件都需要在MyBatis的核心配置文件中进行才能生效！！
<?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>
<environments default="development">
<!--id 标识-->
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<!--mysql驱动程序-->
<property name="driver" value="com.mysql.jdbc.Driver"/>
<!--数据库URL地址-->
<property name="url" value="jdbc:mysql://localhost:3306/mybatis_db?useSSl=true&useUnicode=true&characterEncoding=utf-8"/>
<!--mysql账号-->
<property name="username" value="root"/>
<!--mysql密码-->
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<!--注意：每一个xml配置文件都需要在mybatis的核心配置文件中注册才能生效-->
<mappers>
<mapper resource="cong/hong/mapper/UserMapper.xml"/>
</mappers>
</configuration>
八、编写测试类进行测试
8.1、测试代码：
package cong.hong.mapper;
import cong.hong.pojo.User;
import cong.hong.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
public class UserMapperTest {
@Test
public void test(){
SqlSession session = new MybatisUtils().getSqlSession();
UserMapper mapper = session.getMapper(UserMapper.class);
for (User user : mapper.getUserList()) {
System.out.println(user);
}
if(session!=null){
session.close();
}
}
}
8.2、运行结果