SpringBoot初学（4）– JdbcTemplate和Mybatis

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

#### 28.1.2. 连接到一个生产环境数据库
## 注：其他的连接池可以手动配置。如果你定义自己的DataSource bean，自动配置不会发生。
####
## Spring Boot能够从大多数数据库的url上推断出driver-class-name，那么你就不需要再指定它了。
spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver
## 默认会从url推断driver class
spring.datasource.url=jdbc:oracle:thin:@127.0.0.1:1521:orcl
spring.datasource.username=vergilyn
spring.datasource.password=409839163
## JDNI
# spring.datasource.jndi-name=java:jboss/datasources/customers

/* Spring的JdbcTemplate和NamedParameterJdbcTemplate类是被自动配置的，
 * 你可以在自己的beans中通过@Autowire直接注入它们。
 */
@Repository
public class JdbcTemplateDao {
	@Autowired
	private JdbcTemplate jdbcTemplate;
	@Autowired
	private NamedParameterJdbcTemplate namedJdbc;
	@SuppressWarnings("unused")
	public Long testDao(){
		Map<String,Object> param = new HashMap<String,Object>();
		String sql = "select count(*) from child";
		if(true){
			sql += "where child_name = :name ";
			param.put("name", "周一");
		}
		Long count = this.namedJdbc.queryForObject(sql, param, Long.class);
		System.out.println(count);
		return count;
	}
}

@SpringBootApplication
@RestController
public class DatabaseApplication {
	@Autowired
	private JdbcTemplateDao dao;
	public static void main(String[] args) {
		SpringApplication.run(DatabaseApplication.class, args);
	}
	@RequestMapping("/jdbc")
	public String testDao(){
		return dao.testDao()+"";
	}
}

<dependency>
	<groupId>org.mybatis.spring.boot</groupId>
	<artifactId>mybatis-spring-boot-starter</artifactId>
	<version>1.2.0</version>
</dependency>

<?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">
<configuration>
    <typeAliases>
        <package name="com.vergilyn.demo.springboot.mybatis.domain"/>
    </typeAliases>
    <mappers>
        <mapper resource="config/mybatis/mapper/CityMapper.xml"/>
        <mapper resource="config/mybatis/mapper/HotelMapper.xml"/>
    </mappers>
</configuration>

## spring.datasource.schema=classpath:config/mybatis/init-oracle.sql
mybatis.config-location=classpath:config/mybatis/mybatis-config.xml

@Component
public class CityDao {
	@Autowired
	private SqlSession sqlSession;
	public City selectCityById(long id) {
		return this.sqlSession.selectOne("selectCityById", id);
	}
}

@SpringBootApplication
public class MybatisApplication implements CommandLineRunner {
	public static void main(String[] args) {
		SpringApplication app = new SpringApplication(MybatisApplication.class);
		app.setAdditionalProfiles("mybatis");
		app.run(args);
	}
	@Autowired
	private CityDao cityDao;
	@Override
	public void run(String... args) throws Exception {
		System.out.println(this.cityDao.selectCityById(1));
	}
}

@Mapper
public interface CityMapper {
	// 混用xml形式
	City selectByCityId(int city_id);
	/**
	 * 注解形式不需要通过dao调用*Mapper.xml。所以可以不写dao、*Mapper.xml、mybatis-config.xml
	 * @param i
	 * @return
	 */
	@Select("select * from city where id = #{id}")
	City selectByAnnotation(int i);
}

@Mapper
public interface HotelMapper {
	Hotel selectByHotelId(int city_id);
}

@SpringBootApplication
public class MybatisApplication implements CommandLineRunner {
	public static void main(String[] args) {
		SpringApplication app = new SpringApplication(MybatisApplication.class);
		app.setAdditionalProfiles("mybatis");
		app.run(args);
	}
	@Autowired
	private CityDao cityDao;
	@Autowired
	private HotelMapper hotelMapper;
	@Autowired
	private CityMapper cityMapper;
	@Override
	public void run(String... args) throws Exception {
		System.out.println(this.cityDao.selectCityById(1));
		System.out.println(this.cityMapper.selectByAnnotation(1));
		System.out.println(this.hotelMapper.selectByHotelId(1));
	}
}