我所做的工作和你最近描述的几乎一模一样！下载我用过的文件-

@PutMapping("/{originalFileName}")
public ResponseEntity<ImmutableDocument> send(@PathVariable String originalFileName, InputStream payload) {
    LOG.info("Receiving: {}", originalFileName);
    sendPayload(payload, originalFileName);
    return ResponseEntity.ok().build();
}

我选择了inputstream，因为用字节数组处理内存中1gb的大量文件通常是个坏主意，可能会破坏堆栈！
把那个文件发给目标-

@Autowired
private RestTemplate sendTemplate;

private ResponseEntity<Void> sendPayload(final InputStream payload, final String originalFileName) throws IOException {
// You can send any other bits of information you need on the headers too
        HttpHeaders headers = new HttpHeaders();
        headers.put("originalFileName", originalFileName);
        headers.setContentType(asMediaType(MimeType.valueOf({desired mimetype})));
        headers.setAccept(singletonList(APPLICATION_OCTET_STREAM));
        HttpEntity<Resource> requestEntity = new HttpEntity<>(new InputStreamResource(payload), headers);
        UriComponentsBuilder builder = fromUriString({someurl});
        UriComponents uriComponents = builder.build().encode();
        return sendTemplate.exchange(uriComponents.toUri(), HttpMethod.POST, requestEntity, Void.class);
    }
}

我还为restemplate使用了自己的配置类，并使用消息转换器发送二进制inputstream-

@Configuration
public class RestClientConfiguration {

@Bean
public RestTemplate sendTemplate(ClientHttpRequestFactory clientHttpRequestFactory) {
    return new RestTemplateBuilder()
        .requestFactory(() -> clientHttpRequestFactory)
        .messageConverters(new ResourceHttpMessageConverter())
        .build();
}

}