Android :: Getting File Size Before Input Stream

I want to create a progress Bar for an FTP download. The server where I am downloading the file has all of its directories and files hidden. I want to display the progress of the download. Is there any way I can get the file size? Here is my current code:
FTP client = new FTP Client();
FTP client.setListHiddenFiles
FTP client.connect(host Part);
FTP client.login(user Name, password);
FTPclient.setFileType(FTP.BINARY_FILE_TYPE);
Input Stream instream = FTP client.retrieveFileStream(pathExcludingHostIncludingFirstSlash);
int l;
byte[] tmp = new byte[2048];
int update Counter = 0;
int bytes Downloaded = 0;
while ((l = instream.read(tmp)) != -1) {
Foss.write(tmp, 0, l);
bytes Downloaded+=2048;
update Counter++;
if(update Counter==3){
kilobytes Downloaded=(bytes Downloaded / 1024);
publish Progress((String[])null);
update Counter=0}