• 新增資料庫支援

  在maven中新增元件（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>

• 配置datasource和jpa(application.yml)

  為mysql和jpa新增配置

spring:
  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

注：jpa配置中ddl-auto有多種選擇

• 建立java bean類，為類新增@Entity註解

import javax.persistence.Entity;
import
 
 javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Girl {

    @Id  //將id設為主鍵
    @GeneratedValue //設定Id自增長
    private Integer id ;

    private String name ;

    private Integer age ;
    public Girl() {
    };

    public Integer getId() {
        return id;
    }

    public void setId(Integer 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;
    }
}

注意包不要導錯，包不要導錯，包不要導錯~

• 建立對應介面繼承JpaRepository

import org.springframework.data.jpa.repository.JpaRepository;

//<Girl,Integer>,第一個為需要操作的bean類，第二個引數為bean類中的Id型別，即對應資料庫表中的主鍵型別
public interface GirlRepository extends JpaRepository<Girl,Integer> {
}

• 在Controller中建立例項，通過Jpa呼叫操作資料庫方法。

@RestController
public class GirlController {

    @Autowired
    private GirlRepository girlRepository;

    //通過get方法查詢女生列表
    @GetMapping(value = "/girls")
    public List<Girl> girls(){
        return girlRepository.findAll();
    }

    //通過post方法新增女生列表
    @PostMapping(value = "/girls")
    public Girl girls(@RequestParam("name") String name,@RequestParam("age") Integer age){
        Girl girl = new Girl();
        girl.setAge(age);
        girl.setName(name);
        return girlRepository.save(girl);
    }
}

此外事務管理通過在函式上新增@Transactional註解

@Autowired
    private GirlRepository girlRepository;

    @Transactional
    public void saveTwo(){
        Girl girlA = new Girl();
        girlA.setName("星星");
        girlA.setAge( 12 );
        girlRepository.save(girlA);

        Girl girlB = new Girl();
        girlB.setName("The Apple");
        girlB.setAge( 11 );
        girlRepository.save(girlB);
    }

PS:post方法可以通過下載安裝Postman進行測試，很不錯的工具