在spring mvc@ResponseBody中返回文字JSON字符串

Question

我将对象作为JSON字符串存储在数据库中。我想制作一个公开这些字符串的REST服务。然而，当我编写方法时，我返回的字符串中的引号被转义了。例如,我包含了一个返回字符串的方法,

@RequestMapping(value = "test", method = RequestMethod.GET)
public @ResponseBody
String getTest() {
    return "{\"a\":1, \"b\":\"foo\"}";
}

{
  "value" : "{\"a\":1, \"b\":\"foo\"}"
}

@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    super.configureMessageConverters(converters);
    converters.add(mappingJacksonHttpMessageConverter());
}

@Bean
MappingJacksonHttpMessageConverter mappingJacksonHttpMessageConverter() {
    MappingJacksonHttpMessageConverter mappingJacksonHttpMessageConverter = new MappingJacksonHttpMessageConverter();
    ObjectMapper objectMapper = new ObjectMapper();
    objectMapper.setSerializationInclusion(JsonSerialize.Inclusion.NON_NULL);
    mappingJacksonHttpMessageConverter.setObjectMapper(objectMapper);
    mappingJacksonHttpMessageConverter.setPrettyPrint(true);
    return mappingJacksonHttpMessageConverter;
}

public static class Wrapper {

    @JsonRawValue
    private final String value;
}

Answer 1

这在Jackson 2中起作用（至少）：

@Controller
public class YourController {

    @RequestMapping(..)
    public @ResponseBody Json get() {
        return new Json("{ \"attr\" : \"value\" }");
    }
}

class Json {

    private final String value;

    public Json(String value) {
        this.value = value;
    }

    @JsonValue
    @JsonRawValue
    public String value() {
        return value;
    }
}

不是特别漂亮但很管用。我只希望Spring支持这一点：

@RequestMapping(..)
public @JsonRawValue @ResponseBody String get() {
    // ...
}