post请求用springboot json格式

Question

I have a product table, I have a second option table. I cannot manage to create my options for the product at the same time as I create the product. I tried to create the options individually by creating an option table and a category join table. When I send the options in json format it doesn't work. I get the bad request error and in the console:

JSON parse error: Cannot construct instance of com.pastrycertified.cda.dto.OptionsDto (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value('pie'); nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of com.pastrycertified.cda.dto.OptionsDto (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('pie') at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 2, column: 19] (through reference chain: java.util.LinkedHashMap["typeOption"])]

Thank you for help

data

{
    "typeOption": "product",
    "ingredients": {
        "option1": "test",
        "option2":"test1"
    }
}

controller option

@RestController
@RequestMapping("/options")
@RequiredArgsConstructor
public class OptionsController {

    private final OptionsService optionsService;

    @PostMapping("/")
    public void save(
            @RequestBody Map<String, OptionsDto > options
    ) {
        return ResponseEntity.ok(optionsService.save(options));
    }
}

optionService

public interface OptionsService {

    Options save(OptionsDto options);
}

optionServiceImpl

@Service
@RequiredArgsConstructor
public class OptionsServiceImpl implements OptionsService {


    @Override
    public Options save(OptionsDto options) {

        Options option = OptionsDto.toEntity(options);
        option.setTypeOption(option.getTypeOption());
        option.setIngredients(option.getIngredients());

        return option;
    }
}

optionDto

@Getter
@Setter
@AllArgsConstructor
@Builder
public class OptionsDto {

    private Integer id;

    private String typeOption;

    private String ingredients;

    private String nameCategory;

    private CategoryDto category;

    public static OptionsDto fromEntity(Options options) {

        return OptionsDto.builder()
                .id(options.getId())
                .typeOption(options.getTypeOption())
                .ingredients(options.getIngredients())
                .nameCategory(options.getCategory().getName())
                .build();
    }

    public static Options toEntity(OptionsDto options) {

        return Options.builder()
                .id(options.getId())
                .typeOption(options.getTypeOption())
                .ingredients(options.getIngredients())
                .build();
    }
}

Answer 1

As Jens mentioned, you need a default constructor in the OptionDto class. Also, you must decide whether ingredients is a String or a Map.

In the controller, you are asking for a Map<> but what you pass in the JSON is not a map. Your controller must be asking for an OptionsDto and not a Map.