mybatis框架搭建
1. 创建maven工程并导入坐标
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.itheima</groupId>
<artifactId>day01_eesy_01mybatis</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.16</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.1</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
</project>
2. 创建实体类和dao的接口
package com.itheima.domain;
import java.io.Serializable;
import java.util.Date;
/**
* @Author: lijiahao
* @Description:
* @Data: Create in 21:37 2020/2/22
* @Modified By:
*/
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;
}
package com.itheima.dao;
import com.itheima.domain.User;
import java.util.List;
/**
* @Author: lijiahao
* @Description: 用户的持久层接口
* @Data: Create in 21:42 2020/2/22
* @Modified By:
*/
public interface IUserDao {
List<User> findAll();
}
3. 创建mybatis的主配置文件SqlMapConfig.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">
<!--mybatis的主配置文件-->
<configuration>
<!--配置环境-->
<environments default="mysql">
<!--配置mysql的环境-->
<environment id="mysql">
<!--配置事务的类型-->
<transactionManager type="JDBC"></transactionManager>
<!--配置数据源（连接池）-->
<dataSource type="POOLED">
<!--配置数据库的四个基本信息-->
<property name="driver" value="com.mysql.cj.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/eesy?serverTimezone=Asia/Shanghai&characterEncoding=utf8&useSSL=false" />
<property name="username" value="root" />
<property name="password" value="123456" />
</dataSource>
</environment>
</environments>
<!--指定映射配置文件的位置，映射配置文件指的是每个dao独立的配置文件-->
<mappers>
<mapper resource="com/itheima/dao/IUserDao.xml"/>
</mappers>
</configuration>
4.log4j.properties配置文件
### 设置###
log4j.rootLogger = debug,CONSOLE,LOGFILE
log4j.logger.org.apache.axis.enterprise=FATAL,CONSOLE
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
### 输出ERROR 级别以上的日志到=E://logs/error.log ###
log4j.appender.LOGFILE = org.apache.log4j.FileAppender
log4j.appender.LOGFILE.FILE = F://logs/error.log
log4j.appender.LOGFILE.Append = true
log4j.appender.LOGFILE.layout = org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern = %d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
5.接口映射配置文件 IUserDao.xml
//与接口位置一样
//接口相对位置 java/com/itheima/dao/IUserDao
//接口配置文件相对位置 resources/com/itheima/dao/IUserDao.xml
<?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>
<!--配置查询所有-->
<select id="findAll" resultType="com.itheima.domain.user">
select * from user
</select>
</mapper>
6.测试方法
package com.itheima;
import com.itheima.dao.IUserDao;
import com.itheima.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 javax.annotation.Resource;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* @Author: lijiahao
* @Description:
* @Data: Create in 22:56 2020/2/22
* @Modified By:
*/
public class test {
public static void main(String[] args) throws IOException {
//1.读取配置文件
InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2.创建SqlSessionFactory工厂
SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(in);
//3.使用工厂生产SqlSession对象
SqlSession sqlSession = sqlSessionFactory.openSession();
//4.使用SqlSession创建dao接口的代理对象
IUserDao userDao = sqlSession.getMapper(IUserDao.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
sqlSession.close();
in.close();
}
}
7.注意
接口映射配置文件位置必须和dao接口的包结构相同
接口映射配置文件的mapper标签namespace属性的取值必须是dao接口的全限定类名
接口映射配置文件的操作配置（select），id属性必须是dao接口的方法名
