我的目标是存储和获取个人资料图片。
如何存储：
用户将表单数据发送到邮局/帐户

let formData = new FormData();
formData.append("fullname", "John Wick");
let profile_picture = new File(["foo"], "foo.txt", {
  type: "text/plain",
}); // for simplicity, I use .txt
formData.append("profile_picture", profile_picture);

@RestController
public class AccountController {
  @PostMapping
  public ResponseEntity<String> postAccount(AccountDto accountDto) {
    // do something
  }
}
class AccoutnDto {
  private String profile_picture;
  private String fullname;
  public void getProfile_Picture() {
    return profile_picture;
  }
  // I wish to add javax.constraints or else to prevent upload / download size larger than 128KB.
  public void setProfile_Picture(MultipartFile profile_picture) {
    this.profile_picture = profile_picture;
  }
  public void getFullname() {
    return fullname;
  }
  public void setFullname(String fullname) {
    this.fullname = fullname;
  }
}

如何下载：
用户发送get/profile\U图片

@RestController
public class AccountController {
  @GetMapping("/profile_picture")
  public ResponseEntity<Resource> getAccount() {
    Resource file = // do something...
    return ResponseEntity.ok().header(HttpHeaders.CONTENT_DISPOSITION,
            "attachment; filename=\"" + file.getFilename() + "\"").body(file);
  }
}

我目前的解决方案是在application.yml中添加一个全局配置

spring.servlet.multipart:
  max-file-size: 128KB
  max-request-size: 128KB

我的预期结果是：最大文件大小和最大请求大小只适用于post/account和get/profile\u picture。
我的实际结果是：其他multipartfile对象受到影响。