Spring RestTemplate上传二进制文件

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);

MultiValueMap<String, Object> body = new LinkedMultiValueMap<>();

Resource fileResource = new FileSystemResource("/path/to/file");
body.add("file", fileResource);

HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<>(body, headers);

RestTemplate restTemplate = new RestTemplate();
String url = "http://example.com/upload";
String response = restTemplate.postForObject(url, requestEntity, String.class);