spring boot项目实战之实现与数据库的连接

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

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.26</version>
</dependency>

@Configuration
public class DataSourceConfig {
    @Bean
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource dataSource() {
        return DataSourceBuilder.create().build();
    }
}

@Configuration
public class JdbcConfig {
    @Bean
    public JdbcTemplate jdbcTemplate(DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }
}

@Repository
public class UserDaoImpl implements UserDao {
    @Autowired
    private JdbcTemplate jdbcTemplate;
    @Override
    public User getUserById(int id) {
        String sql = "select * from user where id=?";
        User user = jdbcTemplate.queryForObject(sql, new Object[]{id}, new BeanPropertyRowMapper<>(User.class));
        return user;
    }
}

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDao userDao;
    @Override
    public User getUserById(int id) {
        return userDao.getUserById(id);
    }
}

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService userService;
    @GetMapping("/{id}")
    public User getUserById(@PathVariable int id) {
        return userService.getUserById(id);
    }
}