springboot(20)fastjson设置不序列化字节流

迷南。 2022-05-16 14:04 500阅读 0赞

### 问题 ###

当设置fastjson为springboot的全局序列化工具后，当controller返回二进制字节流时，字节流被fastjson序列化为字符串。

@ResponseBody
    @RequestMapping(value = "/downloadInfo.json")
    public ResponseEntity<byte[]> xx(){ 
        return xx;
    }

*  Preview  
    ![这里写图片描述][20180825141529401]
 *  Response  
    ![这里写图片描述][20180825141543869]

### 解决 ###

fastjson默认的MediaType支持为全部，因此需要指定fastjson支持的MediaType。对于fastjson不支持的`application/octet-stream`使用`ByteArrayHttpMessageConverter`直接发送到前端。

@Bean
    public HttpMessageConverters fastJsonHttpMessageConverters() { 
    	FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
    	FastJsonConfig fastJsonConfig = new FastJsonConfig();
    	fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
    	fastConverter.setFastJsonConfig(fastJsonConfig);
    	List<MediaType> supportedMediaTypes = new ArrayList<>();
    	supportedMediaTypes.add(MediaType.APPLICATION_JSON);
    	supportedMediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
    	supportedMediaTypes.add(MediaType.APPLICATION_ATOM_XML);
    	supportedMediaTypes.add(MediaType.APPLICATION_FORM_URLENCODED);
    	supportedMediaTypes.add(MediaType.APPLICATION_RSS_XML);
    	supportedMediaTypes.add(MediaType.APPLICATION_XHTML_XML);
    	supportedMediaTypes.add(MediaType.APPLICATION_XML);
    	supportedMediaTypes.add(MediaType.TEXT_EVENT_STREAM);
    	supportedMediaTypes.add(MediaType.TEXT_HTML);
    	supportedMediaTypes.add(MediaType.TEXT_MARKDOWN);
    	supportedMediaTypes.add(MediaType.TEXT_PLAIN);
    	supportedMediaTypes.add(MediaType.TEXT_XML);
    	fastConverter.setSupportedMediaTypes(supportedMediaTypes);
    
    	HttpMessageConverter<?> converter = fastConverter;
    	return new HttpMessageConverters(converter,new ByteArrayHttpMessageConverter());
    }

并controller层指定MediaType类型

@RequestMapping(value = "/downloadInfo.json")
    public ResponseEntity<byte[]> xx(){ 
        HttpHeaders headers = new HttpHeaders();
        headers.setContentLength(buffer.length);
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        return new ResponseEntity<>(buffer, headers, HttpStatus.OK);
    }

*  Preview  
    ![这里写图片描述][20180825141629787]
 *  Response  
    ![这里写图片描述][20180825141615834]

[20180825141529401]: /images/20220516/42956cf8a412421388d4e8f7d86386c6.png
[20180825141543869]: /images/20220516/05eb6a74eaeb4a8d8f1ac4e0aa64c814.png
[20180825141629787]: /images/20220516/9ba80e1b27b64a958c2e7f0587946bf8.png
[20180825141615834]: /images/20220516/9983a7db047d4d47af177bc220f1c285.png