Spring Boot 4 MyBatis

Posted 2020-08-09

SpringBoot内使用MyBatis，可以不使用xml映射配置，通过注解方式映射。

pom.xml添加依赖

    <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.1.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.21</version>
        </dependency>

在application.properties配置文件中添加

spring.datasource.url=jdbc:mysql://localhost:3306/test2
spring.datasource.username=root
spring.datasource.password=hongda$123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

这样配置，可以操作数据库中的数据，但是表跟数据库必须自己创建，跟Hibernate有点不一样。

使用MyBatis:

 

public class User {

    private Long id;
    private String name;
    private Integer age;

    public Long getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

操作：

@Mapper
public interface UserMapper {

    @Select("SELECT * FROM user WHERE name = #{name}")
    User findByName(@Param("name") String name);

    @Results({
            @Result(property = "name", column = "name"),
            @Result(property = "age", column = "age")
    })
    @Select("SELECT name, age FROM user")
    List<User> findAll();

    @Insert("INSERT INTO user(name, age) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);

    @Update("UPDATE user SET age=#{age} WHERE name=#{name}")
    void update(User user);

    @Delete("DELETE FROM user WHERE id =#{id}")
    void delete(Long id);

    @Insert("INSERT INTO user(name, age) VALUES(#{name}, #{age})")
    int insertByUser(User user);

    @Insert("INSERT INTO user(name, age) VALUES(#{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER})")
    int insertByMap(Map<String, Object> map);

}

运行:

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = Application.class)
@Transactional
public class ApplicationTests {

    @Autowired
    private UserMapper userMapper;

    @Test
    @Rollback
    public void testUserMapper() throws Exception {
        // insert一条数据，并select出来验证
        userMapper.insert("AAA", 20);
        User u = userMapper.findByName("AAA");
        Assert.assertEquals(20, u.getAge().intValue());
        // update一条数据，并select出来验证
        u.setAge(30);
        userMapper.update(u);
        u = userMapper.findByName("AAA");
        Assert.assertEquals(30, u.getAge().intValue());
        // 删除这条数据，并select验证
        userMapper.delete(u.getId());
        u = userMapper.findByName("AAA");
        Assert.assertEquals(null, u);

        u = new User("BBB", 30);
        userMapper.insertByUser(u);
        Assert.assertEquals(30, userMapper.findByName("BBB").getAge().intValue());

        Map<String, Object> map = new HashMap<>();
        map.put("name", "CCC");
        map.put("age", 40);
        userMapper.insertByMap(map);
        Assert.assertEquals(40, userMapper.findByName("CCC").getAge().intValue());

        List<User> userList = userMapper.findAll();
        for(User user : userList) {
            Assert.assertEquals(null, user.getId());
            Assert.assertNotEquals(null, user.getName());
        }
    }
}

 

http://blog.didispace.com/mybatisinfo/