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Spring整合MyBatis配置Mapper扫描器
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1 配置Mapper扫描器

src/main/resources/applicationContext.xml：

<!-- Mapper扫描器 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
    <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
    <property name="basePackage" value="cn.tedu.springmybatis.dao" />
</bean>

Mapper扫描器：

- 通过SQL会话工厂创建SQL会话；
- 扫描指定包中的所有数据访问接口和对应的Mapper文件；
- 从SQL会话得到数据访问接口的实现类对象(Mapper)，放到Spring容器中；
- Mapper对象的标识(ID)为其所实现数据访问接口类名首字母小写。

2 实体类

/src/main/java/cn.tedu.springmybatis.pojo/User.java：

public class User {
    private int id;
    private String username;
    private String password;
    private String realname;
    private String image;

    public User(int id, String username, String password,
        String realname, String image) {
        this.id = id;
        this.username = username;
        this.password = password;
        this.realname = realname;
        this.image = image;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getRealname() {
        return realname;
    }

    public void setRealname(String realname) {
        this.realname = realname;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }

    @Override
    public String toString() {
        return "User{" +
            "id=" + id +
            ", username='" + username + '\'' +
            ", password='" + password + '\'' +
            ", realname='" + realname + '\'' +
            ", image='" + image + '\'' +
            '}';
    }
}

3 数据访问接口

/src/main/java/cn.tedu.springmybatis.dao/UserDao.java：

public interface UserDao {
    public List<User> getUsers();
}

4 Mapper文件

/src/main/resources/mappers/UserMapper.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 namespace="cn.tedu.springmybatis.dao.UserDao">
    <select id="getUsers" resultType="User">
        select id, username, password, realname, image from t_user
    </select>
</mapper>

5 JUnit依赖

/pom.xml：

<!-- JUnit -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.13.2</version>
    <scope>test</scope>
</dependency>

6 测试

/src/test/java/cn.tedu.springmybatis.dao/UserDaoTest.java：

public class UserDaoTest {
    @Test
    public void testGetUsers() {
        ClassPathXmlApplicationContext context =
            new ClassPathXmlApplicationContext("applicationContext.xml");
        UserDao userDao = context.getBean("userDao", UserDao.class);
        List<User> users = userDao.getUsers();
        assertNotEquals(null, users);
        System.out.println(users);
    }
}

例程：SpringMyBatis