Javascript post:400从angularjs发送post请求时请求错误

我正在写一个上传文件的程序，前端是angularjs，后端是SpringMVC，当我选择文件并单击submit时，我将得到Post400（错误请求）

服务器端的控制器代码是

 @RestController
 public class FileController {

@RequestMapping(value="uploads", method=RequestMethod.POST)
public ModelAndView handleFileUpload(@ModelAttribute Document document,@RequestParam("file") MultipartFile file,
        HttpServletRequest request,HttpServletResponse response) throws IOException{

    System.out.println("in the file Controller");
    //ServletContext context = request.getServletContext();
    byte[] fileBytes = null;
    FileInputStream inputStream = null;
    ServletOutputStream outStream = null;
    BufferedOutputStream stream = null;
    ModelAndView model = new ModelAndView("helloword");
    String myfile = file.getOriginalFilename();

    String message = "the file is with server "+myfile;

    fileBytes = file.getBytes();
    model.addObject("message",message);

    String rootpath = System.getProperty("catalina.home");
    File dir = new File(rootpath +File.separator + "tmpFiles");
    if(!dir.exists()){
        dir.mkdirs();
    }
    System.out.println(dir);
    File serrverFile = new File(dir.getAbsolutePath() + File.separator + "download");
    stream = new BufferedOutputStream(new FileOutputStream(serrverFile));
    stream.write(fileBytes);

    stream.close();
/*  String serverFileName = serrverFile.getAbsolutePath();

    System.out.println(serverFileName);
    File fileDownload = new File(serverFileName);
    try {
        inputStream = new FileInputStream(fileDownload);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }*/

    /*String mimeType = context.getMimeType(serverFileName);
    if(mimeType == null){
        mimeType = "application/octet-stream"; 
    }
    response.setContentType(mimeType);
    response.setContentLength(file.getSize());

    String headerKey = "Content-Deposition";
    String headerValue = String.format("attachment; filename=\"%s\"",file.getName());
    response.setHeader(headerKey, headerValue);

    try {
        outStream = response.getOutputStream();
    } catch (IOException e) {
        e.printStackTrace();
    }

    byte[] buffer = new byte[1000000000];
    int bytesRead = -1;

    try {
        while((bytesRead = inputStream.read(buffer))!= -1){
            outStream.write(buffer, 0 , bytesRead);

        }
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        inputStream.close();
        outStream.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

    */

    return model;
}

如果我使用jsp页面而不是angularjs，那么它工作得很好，但我需要anjularjs中的它。所以我在这里遗漏了什么。请让我知道

 @RestController
 public class FileController {

@RequestMapping(value="uploads", method=RequestMethod.POST)
public ModelAndView handleFileUpload(@ModelAttribute Document document,@RequestParam("file") MultipartFile file,
        HttpServletRequest request,HttpServletResponse response) throws IOException{

    System.out.println("in the file Controller");
    //ServletContext context = request.getServletContext();
    byte[] fileBytes = null;
    FileInputStream inputStream = null;
    ServletOutputStream outStream = null;
    BufferedOutputStream stream = null;
    ModelAndView model = new ModelAndView("helloword");
    String myfile = file.getOriginalFilename();

    String message = "the file is with server "+myfile;

    fileBytes = file.getBytes();
    model.addObject("message",message);

    String rootpath = System.getProperty("catalina.home");
    File dir = new File(rootpath +File.separator + "tmpFiles");
    if(!dir.exists()){
        dir.mkdirs();
    }
    System.out.println(dir);
    File serrverFile = new File(dir.getAbsolutePath() + File.separator + "download");
    stream = new BufferedOutputStream(new FileOutputStream(serrverFile));
    stream.write(fileBytes);

    stream.close();
/*  String serverFileName = serrverFile.getAbsolutePath();

    System.out.println(serverFileName);
    File fileDownload = new File(serverFileName);
    try {
        inputStream = new FileInputStream(fileDownload);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }*/

    /*String mimeType = context.getMimeType(serverFileName);
    if(mimeType == null){
        mimeType = "application/octet-stream"; 
    }
    response.setContentType(mimeType);
    response.setContentLength(file.getSize());

    String headerKey = "Content-Deposition";
    String headerValue = String.format("attachment; filename=\"%s\"",file.getName());
    response.setHeader(headerKey, headerValue);

    try {
        outStream = response.getOutputStream();
    } catch (IOException e) {
        e.printStackTrace();
    }

    byte[] buffer = new byte[1000000000];
    int bytesRead = -1;

    try {
        while((bytesRead = inputStream.read(buffer))!= -1){
            outStream.write(buffer, 0 , bytesRead);

        }
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        inputStream.close();
        outStream.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

    */

    return model;
}