1、新建一个Spring Boot项目

SpringBoot项目

2、添加依赖文件pom.xml

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

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

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

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

3、新建数据库

新建数据库

4、Model层

@Entity  //表示是一个实体类，对应数据库中一个表
@Data //Lombok，使用这个注解不用自己写Getter/Setter
@Table(name = "book_06")
public class Book06 {
    /**
     * 书籍ID
     */
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    /**
     * 书籍名称
    */ 
    private String title;
    /**
     * 图片URL
     */
    private String imgUrl;
    /**
     * 作者
     */
    private String author;
    /**
     * 翻译者
     */
    private String translator;
    /**
     * 价格
     */
    private double price;
    /**
     * 出版社名称
     */
    private String publisherName;
}

5、Dao层

@Repository
public interface Book06Repository extends JpaRepository<Book06, Integer> {
}

6、Controller层

@Api("书籍管理接口")
@RestController
public class Book06Controller {

    @Autowired
    private Book06Repository productRepository;

    /**
    * @Description: 查询所有
    * @Author: wangxianlin
    * @Date: 2020/2/22 4:25 PM
    */
    @ApiOperation("查询所有书籍")
    @GetMapping("/product")
    private List<Book06> list() {
        return productRepository.findAll();
    }

    /**
    * @Description: 新增
    * @Author: wangxianlin
    * @Date: 2020/2/22 4:25 PM
    */
    @ApiOperation("新增书籍")
    @PostMapping(value = "/product")
    private Book06 add(Book06 item) {
        return productRepository.save(item);
    }

    /**
    * @Description: 根据ID查询
    * @Author: wangxianlin
    * @Date: 2020/2/22 4:26 PM
    */
    @ApiOperation("根据ID查询书籍")
    @GetMapping(value = "/product/{id}")
    public Book06 getOne(@PathVariable("id") Integer id) {
        return productRepository.findById(id).get();
    }

    /**
    * @Description: 根据ID删除
    * @Author: wangxianlin
    * @Date: 2020/2/22 4:26 PM
    */
    @ApiOperation("根据ID删除书籍")
    @DeleteMapping(value = "/product/{id}")
    public void delete(@PathVariable("id") Integer id) {
        productRepository.deleteById(id);
    }

    /**
    * @Description: 更新
    * @Author: wangxianlin
    * @Date: 2020/2/22 4:26 PM
    */
    @ApiOperation("更新书籍")
    @PutMapping(value = "/product")
    public Book06 put(Book06 item) {
        return productRepository.save(item);
    }

}

7、config层

@Configuration
public class Swagger2 {
    @Bean
    public Docket createRestApi() {
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo())
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.dmt.jpa06"))
                .paths(PathSelectors.any())
                .build();
    }

    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("JPA测试")
                .description("简单优雅的restful风格")
                .termsOfServiceUrl("www.wangxianlin@icloud.com")
                .version("1.0")
                .build();
    }

}

8、测试

• 启动项目
  浏览器输入地址：http://127.0.0.1:8080/swagger-ui.html

Swagger2测试页面

• 新增书籍

  
  新增书籍

• 查询所有的书籍

  
  查询所有书籍

--修改书籍

修改书籍

-根据ID查询书籍

image.png

• 删除书籍

  
  根据ID删除书籍

9、发现问题解决办法

• 项目启动报如下的错误

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'book06Controller': Unsatisfied dependency expressed through field 'productRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'book06Repository': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Not a managed type: class com.dmt.jpa06.model.Book06

• 解决办法：
  这个包导入错误！

  
  image.png

正确包：javax.persistence.Entity