java - Spring boot 的 Postman Post 请求会保存整个 JSON 正文，而不仅仅是字段值。我该如何解决？

Question

postman

我的 header “Content-Type”是“application/json”，我用 JSON 发送它， 看起来像这样...

{
    "category": "House Maintenance"
}

申请

Category.java(模型)

@Data
@Entity
@Table(name = "Categories")
public class Category implements Serializable{
    private static final long serialVersionUID = -8577891700634111561L;

    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", nullable = false)
    private Long id;

    @Column(name = "category", nullable = false)
    private String category;

    public Category(String category){
        super();
        this.category = category;
    }

    public Category(){

    }
}

CategoryServiceImpl.java(保存方法)

@Override
  public void save(Category newCategory) {
      categoryRepository.save(newCategory);
  }

CategoryController.java(请求)

@RequestMapping(value = "/categories", method = RequestMethod.POST)
    public void addCategory(@RequestBody String categoryName){
        Category newCategory = new Category(categoryName);
        categoryService.save(newCategory);
    }

Answer 1

您在 Controller 方法中将请求转换为字符串，因此您收到请求的整个正文并将类别字段设置为整个 json 字符串。

您想要做的是 Spring Boot 已经为您提供了转换后的 dto:

@RequestMapping(value = "/categories", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
public void addCategory(@RequestBody Category category){
  categoryService.save(category);
}

如果您不想将实体与请求耦合，则需要引入一个额外的类，例如CreateCategoryDto:

@Data
public class CreateCategoryDTO{

  @JsonProperty(value = "category") 
  private String category;
}

(我假设您使用的是 Lombok 和 Jackson。添加注释 @JsonProperty(value = "category") 只是为了说明如何将 Java 字段名称与 Json 名称解耦。 )

Controller 就变成了

@RequestMapping(value = "/categories", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
public void addCategory(@RequestBody CreateCategoryDto categoryDto){

  Category newCategory = new Category(categoryDto.getCategory());
  categoryService.save(newCategory);
}