Uploaded filename encoding issue for Japanese and Chinese

I am currently using the jQuery-File-Upload. I may upload some files with a Japanese or Chinese file name, and I can see that the file name is for example, "お疲れ様です.txt" or "测试文档.txt" in browser's debug mode, but in the backend(Java), they become "ã�Šç–²ã‚Œæ§˜ã�§ã�™.txt" and "测试文档.txt".
I once tried to set formAcceptCharset to UTF-8 but it does not work.
Question:
How to get the correct file name in Java side when parsing the MultipartFormData?

Thanks in advance.

BTW, The following is my data

-----------------------------25382434931419
Content-Disposition: form-data; name="file"; filename="�疲れ様��.txt"
Content-Type: text/plain
....

Add the Java codes
In fact I did nothing in Java side currently,

@POST
@Consumes(MediaType.MULTIPART_FORM_DATA)
public String upload(InMultiPart inMP) {
    while (inMP.hasNext()) {
        InPart part = inMP.next();
        MultivaluedMap<String, String> headers = part.getHeaders();
        String fileName = null;
        if (!headers.containsKey("Content-Disposition")) {
            continue;
        } else {
            // get the file name here
            fileName = parseFileName(headers.getFirst("Content-Disposition"));
        }
        //.....
    }
    //......
}

private String parseFileName(String disposition) {
    int fileNameIndex = disposition.indexOf("filename=");
    if (fileNameIndex < 0) {
        return null;
    }
    int start = disposition.indexOf("\"", fileNameIndex) + 1;
    int end = disposition.indexOf("\"", start);
    return  disposition.substring(start, end);
}