mybatis的入门程序
- 在idea中新建maven工程
- 添加依赖坐标，打开pom.xml文件，添加mybatis,mysql,junit,log4j的坐标依赖
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.10</version>
</dependency>
</dependencies>
- 新建数据库mybaties,建一个user表
CREATE TABLE `mybaties` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '用户名称',
`birthday` datetime NULL DEFAULT NULL COMMENT '生日',
`sex` char(1) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '性别',
`address` varchar(256) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '地址',
PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 49 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;
- 在src下mian目录下新建一个一个User类，放在com.liquan.domain
package com.liquan.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @auth nan
* @create 2019-12-23 21:12
*/
public class User implements Serializable {
private Integer id;
private String username;
private Date birthday;
private String sex;
private String address;
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 Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", birthday=" + birthday +
", sex='" + sex + '\'' +
", address='" + address + '\'' +
'}';
}
}
- 5 新建UserDao接口，放在com.liquan.dao包
package com.liquan.dao;
import com.liquan.domain.User;
import java.util.List;
/**
* @auth nan
* @create 2019-12-22 18:45
*/
public interface UserDao {
/***
* 查询所有的接口
* @return
*/
List<User> findAll();
}
- 在resource下新建SqlMapConfig.xml,内容如下：
<?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>
<!--配置mysql的环境-->
<environments default="mysql">
<environment id="mysql">
<!--配置事务的类型-->
<transactionManager type="JDBC"></transactionManager>
<!--配置数据源（这里配置连接池）-->
<dataSource type="POOLED">
<!--配置连接数据库的四个基本属性-->
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mybaties"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<!--指定映射配置文件的位置-->
<mappers>
<mapper resource="com/liquan/dao/UserDao.xml"></mapper>
</mappers>
</configuration>
- 7 在resouce下新建UserDao.xml位于com.liquan.dao目录下
<?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.liquan.dao.UserDao">
<select id="findAll" resultType="com.liquan.domain.User">
select * from user
</select>
</mapper>
- 8 在test目录下新建一个测试类MybaitsTest,如下：
package com.liquan.test;
import com.liquan.dao.UserDao;
import com.liquan.domain.User;
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;
import java.util.List;
/**
* @auth nan
* @create 2019-12-23 21:26
*/
public class MybatisTest {
public static void main(String[] args) throws Exception {
InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.创建SqlSessionFactory工厂
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(in);
//3.使用工厂生产SqlSession对象
SqlSession session = factory.openSession();
//4.使用SqlSession创建Dao接口的代理对象
UserDao userDao = session.getMapper(UserDao.class);
//5.使用代理对象执行方法
List<User> users = userDao.findAll();
for(User user : users){
System.out.println(user);
}
//6.释放资源
session.close();
in.close();
}
}
运行测试类就可以得到user
