springboot之數據庫操作（1）

springboot之數據庫操作1——（spring data jpa）

                																			——"我靠"

剛學習了springboot的數據庫操作，我的腦子裏就兩個字——“我靠”。
這操作，相對於其他java框架來說簡直是太簡單了，比起jfinal數據庫操作，我感覺都不差,更不要說mybatis了。

jpa是什麼？

步驟

1.添加相關jar包/依賴

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
     <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>

2.添加配置文件

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

spring.jpa.properties.hibernate.hbm2ddl.auto=update
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.show-sql= true

3.添加實體類和Dao

實體類：用來和數據庫的表進行關聯。

@Entity
public class User implements Serializable {

	private static final long serialVersionUID = 1L;
	@Id
	@GeneratedValue
	private Long id;
	@Column(nullable = false, unique = true)
	private String userName;
	@Column(nullable = false)
	private String passWord;
	@Column(nullable = false, unique = true)
	private String email;
	@Column(nullable = true, unique = true)
	private String nickName;
	@Column(nullable = false)
	private String regTime;

	//省略getter settet方法、構造方法

}

Dao：一個面向對象的數據庫接口，用來調用操作數據庫的方法的。

public interface UserRepository extends JpaRepository<User, Long> {
    User findByUserName(String userName);
    User findByUserNameOrEmail(String username, String email);
}

4.測試

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(Application.class)
public class UserRepositoryTests {

	@Autowired
	private UserRepository userRepository;

	@Test
	public void test() throws Exception {
		Date date = new Date();
		DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG);        
		String formattedDate = dateFormat.format(date);
		
		userRepository.save(new User("aa1", "[email protected]", "aa", "aa123456",formattedDate));
		userRepository.save(new User("bb2", "[email protected]", "bb", "bb123456",formattedDate));
		userRepository.save(new User("cc3", "[email protected]", "cc", "cc123456",formattedDate));

		Assert.assertEquals(9, userRepository.findAll().size());
		Assert.assertEquals("bb", userRepository.findByUserNameOrEmail("bb", "[email protected]").getNickName());
		userRepository.delete(userRepository.findByUserName("aa1"));
	}

}

具體：http://www.ityouknow.com/springboot/2016/02/03/spring-boot-web.html