FIrstly, you write code doesn't check how much was actually read into the buffer -- the code currently writes the whole buffer which may not have been fully read. This is bound to cause corruption. I think that's the root cause of your issue. Fix this first.
while (off < myFileSize) {
int chunkLength = myFileStream.read(mydataBuf, 0, Math.min(myFileSize - off, bufSize));
if (chunkLength == -1) {
// Input stream reached its end -- handle this situation appropriately.
// In this case throwing an EOFException is probably a good idea
throw new EOFException("Input stream closed prematurely");
}
myOutputStream.write(mydataBuf, 0, chunkLength);
off += chunkLength;
}
myOutputStream.flush();
Since reading and writing are performed sequentially, the read rate will be automatically throttled to the write rate -- you aren't attempting to read until the previous write operation completes. The code you have right now (if you add modify it to write out from the buffer only as much as was read in) should work just fine. It will read some data into the beginning of the buffer, then write all of this data out. Only when the data has been sent to the lower layers, will it read more data into the beggining of the buffer again, and so forth.
If you aren't reading fast enough, TCP will automatically tell the peer to send at lower rate. No new incoming data will overwrite old data in the buffer.
If you want to buffer some data before writing it out, you can simply wrap the output stream into a BufferedOutputStream. Usually, this class will not write anything out to the lower layers unless its buffer is filled, or unless you explicitly tell it so by invoking flush() or close().
