SpringBoot and JPA

Deletions achieve data change search

 

 

 

 1. Import dependence

 

<!--  引入mysql需要的依赖  -->
    <dependency>  
            <groupId>mysql</groupId>  
            <artifactId>mysql-connector-java</artifactId>  
   </dependency>  
    <!--  引入spring data jpa需要的依赖  -->
    <dependency>  
            <groupId>org.springframework.boot</groupId>  
            <artifactId>spring-boot-starter-data-jpa</artifactId>  
   </dependency>  

 

2. Create the src / main / application.yml file in the resource

 

 

Four connection parameters database ## 
Spring: 
  DataSource: 
    Driver-class-name: com.mysql.jdbc.Driver 
    URL: JDBC: MySQL: /// springbootjpa 
    username: the root 
    password: 123 
## Table generation strategy jpa 
  jpa: 
    Hibernate : 
      DDL-Auto: Update

 

 

3. Create entity classes Grade

 

 

@Entity
public class Grade {
    @Id
    @GeneratedValue(strategy= GenerationType.AUTO)
    private Integer grade_id;
    private String grade_name;

    public Integer getGrade_id() {
        return grade_id;
    }

    public void setGrade_id(Integer grade_id) {
        this.grade_id = grade_id;
    }

    public String getGrade_name() {
        return grade_name;
    }

    public void setGrade_name(String grade_name) {
        this.grade_name = grade_name;
    }
}

 

 

4. Create dao layer

 

 

 

 

 

 

 

/ ** 
 * CrudRepository <entity, the primary key data type> 
 * / 
@Repository 
public interface IGradeMapper the extends CrudRepository <Grade, Integer> { 
}

 

 

5. Create a service layer interface

 

public interface IGradeService {
    public Grade insertGrade(Grade grade);


    public Grade updateGrade(Grade grade);

    public void deleteGrade(Integer id);


    public Iterable<Grade> getAll();
}

 

6. Create a service implementation class

 

@Service("iGradeService")
public class IGradeServcieImpl implements IGradeService {
    @Resource
    private IGradeMapper iGradeMapper;


    @Override
    public Grade insertGrade(Grade grade) {
        return iGradeMapper.save(grade);
    }

    @Override
    public Grade updateGrade(Grade grade) {
        return iGradeMapper.save(grade);
    }

    @Override
    public void deleteGrade(Integer id) {
        iGradeMapper.delete(id);

    }

    @Override
    public Iterable<Grade> getAll() {
        return iGradeMapper.findAll();
    }

}

 

7. Create controller layer

 

@RestController
@RequestMapping("/IGradeController")
public class IGradeController {
    @Resource
    private IGradeService iGradeService;

    //新增数据
    @RequestMapping("/insertGrade")
    public Grade insertGrade(){
        Grade grade=new Grade();
        grade.setGrade_name("S1");
        return iGradeService.insertGrade(grade);
    }

    @RequestMapping("/updateGrade")
    public Grade updateGrade(){
        Grade grade=new Grade();
        grade.setGrade_id(1);
        grade.setGrade_name("S2");
        return iGradeService.updateGrade(grade);
    }

    @RequestMapping("/deleteGrade")
    public void deleteGrade(){

        iGradeService.deleteGrade(1);
    }

    @RequestMapping("/getAllGrade")
    public Iterable<Grade> getAllGrade(){
       return  iGradeService.getAll();
    }
}

 

8. Create a test class StartSpringBoot

 

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

 

9. browser test

 

 

 

 

 

 

(1) Basic theory

 

JPA is referred to as the Java Persistence API, the Chinese name of the Java Persistence API, is JDK 5.0 annotations or XML description of the object - mapping between relational tables, and run the entity object persistence to the database.