415 Unsupported Media Type during csv upload

Question

I would like to upload csv file from client (Angular) and parse it on server (Java). That's how my java enpoint looks like:

    @POST
    @Path( "/csv-objects" )
    @Consumes( MediaType.MULTIPART_FORM_DATA )
    public Response getCsvObjects(
        @FormDataParam( "file" ) InputStream aCsv,
        @FormDataParam( "file" ) FormDataContentDisposition aCsvDetails
    )
    {
        return Response.ok(csvImporter.getObjectsFromCsv( aCsv ) );
    }

Looks exactly like example reffered here LINK

On the opposite client side:

  public importFromCsv(file: File): Observable<any> {
    const uploadedFile: FormData = new FormData();
    uploadedFile.append( 'file', file, file.name);
    return this.httpClient.post(`${this.DEFAULT_ENDPOINT}/csv-objects`, uploadedFile);
}

I have also tried use Blob:

public importFromCsv(file: File): Observable<any> {
    const uploadedFile: FormData = new FormData();
        uploadedFile.append( 'file', new Blob([file], {type: 'text/csv'}) );
    return this.httpClient.post(`${this.DEFAULT_ENDPOINT}/csv-objects`, uploadedFile);
}

or add headers Content-Type: multipart/form-data but there is no result - always getting 415 Unsupported Media Type

What can be wrong?