java - Determine the size of an InputStream

Question

My current situation is: I have to read a file and put the contents into InputStream. Afterwards I need to place the contents of the InputStream into a byte array which requires (as far as I know) the size of the InputStream. Any ideas?

As requested, I will show the input stream that I am creating from an uploaded file

InputStream uploadedStream = null;
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
java.util.List items = upload.parseRequest(request);      
java.util.Iterator iter = items.iterator();

while (iter.hasNext()) {
    FileItem item = (FileItem) iter.next();
    if (!item.isFormField()) {
        uploadedStream = item.getInputStream();
        //CHANGE uploadedStreambyte = item.get()
    }
}

The request is a HttpServletRequest object, which is like the FileItemFactory and ServletFileUpload is from the Apache Commons FileUpload package.

Answer 1

This is a REALLY old thread, but it was still the first thing to pop up when I googled the issue. So I just wanted to add this:

InputStream inputStream = conn.getInputStream();
int length = inputStream.available();

Worked for me. And MUCH simpler than the other answers here.

Warning This solution does not provide reliable results regarding the total size of a stream. Except from the JavaDoc:

Note that while some implementations of {@code InputStream} will return * the total number of bytes in the stream, many will not.