springboot数据库操作及事物管理操作例子

一.配置文件

pom.xml

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

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

application.yml

spring:
  profiles:
    active: dev
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/dbgirl
    username: root
    password: 123456
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

application-dev.yml

server:
  port: 8080
girl:
  cupSize: B
  age: 18

active: dev 这句active后面的dev代码加载的是application-dev.yml这个配置.

ddl-auto: update这句ddl-auto后面是的update代表的是更新这个表,如果的create的话,代表删掉原来的表重新建表,配置完这些之后就不需要我们自己建表
,数据库会给我们建好相应的表.

二.代码

Girl.java

 */
@Entity
public class Girl {

    @Id
    @GeneratedValue
    private Integer id;

    @NotBlank(message = "这个字段必传")
    private String cupSize;

    @Min(value = 18, message = "未成年少女禁止入门")
//    @NotNull
//    @Max()
//    @Length()
    private Integer age;

    @NotNull(message = "金额必传")
    private Double money;

    public Girl() {
    }

    public Integer getId() {
        return id;
    }

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

    public String getCupSize() {
        return cupSize;
    }

    public void setCupSize(String cupSize) {
        this.cupSize = cupSize;
    }

    public Integer getAge() {
        return age;
    }

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

    public Double getMoney() {
        return money;
    }

    public void setMoney(Double money) {
        this.money = money;
    }
}

程序是的入口
GirlApplication.java

@SpringBootApplication
public class GirlApplication {

    public static void main(String[] args) {
        SpringApplication.run(GirlApplication.class, args);
    }
}

GirlProperties.java

@Component
@ConfigurationProperties(prefix = "girl")
public class GirlProperties {

    private String cupSize;

    private Integer age;

    public String getCupSize() {
        return cupSize;
    }

    public void setCupSize(String cupSize) {
        this.cupSize = cupSize;
    }

    public Integer getAge() {
        return age;
    }

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

GirlController.java

@RestController
public class GirlController {

    @Autowired
    private GirlRepository girlRepository;

    @Autowired
    private GirlService girlService;

    /**
     * 查询所有女生列表
     * @return
     */
    @GetMapping(value = "/girls")
    public List<Girl> girlList() {
        return girlRepository.findAll();
    }

    /**
     * 添加一个女生
　　　　 *
     * @return
     */
    @PostMapping(value = "/girls")
    public Girl girlAdd(@Valid Girl girl, BindingResult bindingResult) {
        if (bindingResult.hasErrors()) {
            System.out.println(bindingResult.getFieldError().getDefaultMessage());
            return null;
        }

        girl.setCupSize(girl.getCupSize());
        girl.setAge(girl.getAge());

        return girlRepository.save(girl);
    }

    //查询一个女生
    @GetMapping(value = "/girls/{id}")
    public Girl girlFindOne(@PathVariable("id") Integer id) {
        return girlRepository.findOne(id);
    }

    //更新
    @PutMapping(value = "/girls/{id}")
    public Girl girlUpdate(@PathVariable("id") Integer id,
                           @RequestParam("cupSize") String cupSize,
                           @RequestParam("age") Integer age) {
        Girl girl = new Girl();
        girl.setId(id);
        girl.setCupSize(cupSize);
        girl.setAge(age);

        return girlRepository.save(girl);
    }

    //删除
    @DeleteMapping(value = "/girls/{id}")
    public void girlDelete(@PathVariable("id") Integer id) {
        girlRepository.delete(id);
    }

    //通过年龄查询女生列表
    @GetMapping(value = "/girls/age/{age}")
    public List<Girl> girlListByAge(@PathVariable("age") Integer age) {
        return girlRepository.findByAge(age);
    }

    @PostMapping(value = "/girls/two")
    public void girlTwo() {
        girlService.insertTwo();
    }
}

最上面添加女生,这个是通过传入Gril这个参数,通过点出get方法来获取对应的属性值,推荐这个写法.

GirlRepository .java

public interface GirlRepository extends JpaRepository<Girl, Integer> {

    //通过年龄来查询
    public List<Girl> findByAge(Integer age);
}

GirlService.java

@Service
public class GirlService {

    @Autowired
    private GirlRepository girlRepository;

    @Transactional
    public void insertTwo() {
        Girl girlA = new Girl();
        girlA.setCupSize("A");
        girlA.setAge(18);
        girlRepository.save(girlA);


        Girl girlB = new Girl();
        girlB.setCupSize("BBBB");
        girlB.setAge(19);
        girlRepository.save(girlB);
    }
}

GirlService.java这个类是用来测试事物管理.
在这个类的某个方法上加上@Transactional这个注解说明这个方法就已经交由springboot事物管理.有事物管理和没有事物管理的区别是:
有事物管理这个方法内有一个操作失败,如这个类的插入操作,有一个插入失败,这个方法内的操作全部失败.
如果没有事物就只有失败的那一个操作失败.
一般用于同时操作多条数据,只有查询的时候不加事物.