mybatis第一个项目

 1 public class Test {
 2     public static void main(String[] args) throws IOException {
 3         // 1.读取配置文件
 4         InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
 5         //2.创建SQLSessionFactory工厂
 6         SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
 7         SqlSessionFactory factory = builder.build(in);
 8         //3.使用工厂生产SQLSession对象
 9         SqlSession session = factory.openSession();
10         //4.使用SQLSession创建Dao接口的代理对象
11         IUserDao userDao = session.getMapper(IUserDao.class);
12         //5.使用代理对象执行方法
13         List<User> users = userDao.findAll();
14         for (User user : users) {
15             System.out.println(user);
16         }
17         //6.释放资源
18         session.close();
19         in.close();
20     }
21 }

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <!DOCTYPE configuration
 3         PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
 4         "http://mybatis.org/dtd/mybatis-3-config.dtd">
 5 <!--mybatis的主配置文件-->
 6 <configuration>
 7     <!--配置环境-->
 8     <environments default="mysql">
 9         <!--配置mysql的环境-->
10         <environment id="mysql">
11             <!--配置事务类型-->
12             <transactionManager type="JDBC"></transactionManager>
13             <!--配置数据源（连接池）-->
14             <dataSource type="POOLED">
15                 <!--配置连接数据库的4个基本信息-->
16                 <property name="driver" value="com.mysql.jdbc.Driver"/>
17                 <property name="url" value="jdbc:mysql://localhost:3306/db1"/>
18                 <property name="username" value="root"/>
19                 <property name="password" value="root"/>
20             </dataSource>
21         </environment>
22     </environments>
23     <!--指定映射文件的位置 ，映射配置文件指的是每个dao独立的配置文件-->
24     <mappers>
25         <mapper resource="com/itheima/dao/IUserDao.xml"/>
26     </mappers>
27 </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  <mapper namespace="com.itheima.dao.IUserDao">
 6     <!--配置查询所有-->
 7     <select id="findAll" resultType="com.itheima.domain.User">
 8         select * from user
 9     </select>
10 </mapper>

package com.itheima.domain;

import java.io.Serializable;
import java.util.Date;

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 + ‘\‘‘ +
                ‘}‘;
    }
}

package com.itheima.dao;

import com.itheima.domain.User;

import java.util.List;

public interface IUserDao {
    List<User> findAll();
}