Java – read from InputStream and write to OutputStream

This should be very simple. I searched Google, but I didn't see anyone mention the problems I noticed Everything I've seen is basically the same like this:

byte [] buffer = new byte[256];
int bytesRead = 0;
while((bytesRead = input.read(buffer)) != -1)
{
    output.write(buffer,bytesRead);
}

I know that read () returns - 1 when EOF is reached, but what if the file is smaller than the buffer or even the same size? For example, a 200 byte file is being read in I assume it reads 200 bytes, but returns - 1 This matches JavaDocs, but it also means that write () will never be called I wanted to actually tell me that it reads 200 bytes and returns - 1 at the next iteration

How can I solve this "problem"?

Solution

For reference only, guava has bytestreams Copy (InputStream, OutputStream), you can use it directly or see how it solves this problem