初学MyBatis

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <project xmlns="http://maven.apache.org/POM/4.0.0"
 3          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 5     <modelVersion>4.0.0</modelVersion>
 6 
 7     <groupId>com.itheima</groupId>
 8     <artifactId>day01_eesy_01mybatis</artifactId>
 9     <version>1.0-SNAPSHOT</version>
10 
11 <!--    配置打包方式-->
12     <packaging>jar</packaging>
13 
14 
15 <!--    导入mybatis依赖-->
16     <dependencies>
17         <dependency>
18             <groupId>org.mybatis</groupId>
19             <artifactId>mybatis</artifactId>
20             <version>3.4.5</version>
21         </dependency>
22 
23 <!--        导入mysql依赖-->
24         <dependency>
25             <groupId>mysql</groupId>
26             <artifactId>mysql-connector-java</artifactId>
27             <version>5.1.6</version>
28         </dependency>
29 
30 <!--        导入日志-->
31         <dependency>
32             <groupId>log4j</groupId>
33             <artifactId>log4j</artifactId>
34             <version>1.2.12</version>
35         </dependency>
36 
37 <!--    导入单元测试-->
38         <dependency>
39             <groupId>junit</groupId>
40             <artifactId>junit</artifactId>
41             <version>4.10</version>
42             <scope>test</scope>
43         </dependency>
44 
45     </dependencies>
46 
47 
48 
49 </project>

 1 package com.itheima.domain;
 2 
 3 import java.io.Serializable;
 4 import java.util.Date;
 5 
 6 public class User implements Serializable {
 7     private Integer id;
 8     private String username;
 9     private Date birthday;
10     private String sex;
11     private String address;

1 package com.itheima.dao;
2 import com.itheima.domain.User;
3 import java.util.List;
4 public interface IUserDao {
5     
6     List<User> findAll();
7     
8 }

<?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">
<!--            配置事物的类型-->
            <transactionManager type="JDBC"></transactionManager>
<!--            配置数据源连接池-->
            <dataSource type="POOLED">
<!--                配置连接数据库的四个基本数据-->
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/eesy_mybatis"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>

    <!-- 告知 mybatis 映射配置的位置 -->
    <mappers>
        <mapper resource="com/itheima/dao/IUserDao.xml"></mapper>
    </mappers>
</configuration>

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <!DOCTYPE mapper
 3         PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
 4         "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 5 
 6 
 7  <mapper namespace="com.itheima.dao.IUserDao">
 8 <!--    配置查询所有-->
 9     <select id="findAll" resultType="com.itheima.domain.User">
10         select * from user;
11     </select>
12 
13 </mapper>

 1   //1.读取配置文件
 2         InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
 3         //2.创建SqlSessionFactory工厂
 4         SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
 5         SqlSessionFactory factory = builder.build(in);
 6         //3.使用工厂生产session对象
 7         SqlSession session = factory.openSession();
 8         //4.使用session对象创建dao代理对象
 9         IUserDao iUserDao = session.getMapper(IUserDao.class);
10         //5.使用代理对象执行方法
11         List<User> users = iUserDao.findAll();
12         for(User user : users){
13             System.out.println(user);
14         }
15         //6.释放资源
16         session.close();
17         in.close();