Spring Boot统一返回体的踩坑记录

@RestControllerAdvice("cn.felord.controller")

@RestController
@RequestMapping("/foo")
public class FooController extends BaseController {
 //todo 省略
}    

@RestControllerAdvice(assignableTypes = BaseController.class)

boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType);

@Documented
@Inherited
@Target({ElementType.ANNOTATION_TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface IgnoreRestBody {
}

@Override
public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) {
    return !returnType.hasMethodAnnotation(IgnoreRestBody.class);
}

@GetMapping("/get")
public String getStr(){
    //返回了一个字符串
    return "felord.cn";
}

{
    code: 200,
    data: "felord.cn",
    msg: "返回成字符串",
}

@Configuration(proxyBeanMethods = false)
public class SpringMvcConfiguration implements WebMvcConfigurer {
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        // 解决 String 统一封装RestBody的问题
        converters.add(0, new MappingJackson2HttpMessageConverter());
    }
}

@Configuration(proxyBeanMethods = false)
public class SpringMvcConfiguration implements WebMvcConfigurer {
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        // 解决 String 统一封装RestBody的问题
        HttpMessageConverter<?> httpMessageConverter = converters.get(7);
        if (!(httpMessageConverter instanceof MappingJackson2HttpMessageConverter)) {
            // 确保正确，如果有改动就重新debug
            throw new RuntimeException("MappingJackson2HttpMessageConverter is not here");
        }
        converters.add(0, httpMessageConverter);
    }
}

{
    code: 200,
    data: ['a','b'],
    msg: "返回成字符串",
}

private boolean checkPrimitive(Object body) {
    Class<?> clazz = body.getClass();
    return clazz.isPrimitive()
            || clazz.isArray()
            || Collection.class.isAssignableFrom(clazz)
            || body instanceof Number
            || body instanceof Boolean
            || body instanceof Character
            || body instanceof String;
}

      // 增强扩展性
        if (checkPrimitive(body)) {
            return RestBody.okData(Collections.singletonMap("result", body));
        }