private void setSendPacketAddress(DatagramPacket sendPacket, DatagramPacket receivePacket) {
// Tell the client to send more data
sendPacket.setAddress(receivePacket.getAddress());
sendPacket.setPort(receivePacket.getPort());
}
@Override
public void run() {
try {
// Create a packet for sending data
DatagramPacket sendPacket = new DatagramPacket(buffer, buffer.length);
OutputStream outputStream = null;
String fileName = "";
boolean createFile = true;
int bytesReceived = 0;
long totalBytesReceived = 0;
long fileSize = 0;
socket.receive(receivePacket);
// Display the client number
textArea.append("Starting thread for UDP client " + clientNo + " at " + new Date() + '\n');
textArea.append(
"The client host name is "
+ receivePacket.getAddress().getHostName()
+ " and port number is "
+ receivePacket.getPort()
+ '\n');
// Continuously serve the client
while (true) {
bytesReceived = receivePacket.getLength();
if (bytesReceived
> 0) { // Get the file transmission header from the initial client packet
String transmitHeader = new String(receivePacket.getData(), 0, bytesReceived);
// transmitHeader = transmitHeader.substring(0, bytesReceived).trim().;
String[] header = transmitHeader.split(HEADER_DEL);
fileSize = Long.parseLong(header[0]);
fileName = header[1];
// Send receipt acknowledgment back to the client. Just send back the number of bytes
// received.
setSendPacketAddress(sendPacket, receivePacket);
sendPacket.setData(String.valueOf(bytesReceived).getBytes());
socket.send(sendPacket);
}
while (totalBytesReceived < fileSize) {
// Wait for client to send bytes
// socket.setSendBufferSize(BUFFER_SIZE);
socket.receive(receivePacket);
bytesReceived = receivePacket.getLength();
if (totalBytesReceived == 0) {
if (createFile) { // Get a unique name for the file to be received
// fileName = getUniqueFileName();
fileName = textFolder.getText() + fileName;
outputStream = createFile(fileName);
createFile = false;
textArea.append("Receiving file from client.\n");
}
// Write bytes to file
outputStream.write(receivePacket.getData(), 0, bytesReceived);
} else {
if (outputStream != null) { // Write bytes to file, if any
outputStream.write(receivePacket.getData(), 0, bytesReceived);
}
}
// Increment total bytes received
totalBytesReceived += bytesReceived;
// Tell the client to send more data. Just send back the number of bytes received.
sendPacket.setData(String.valueOf(bytesReceived).getBytes());
socket.send(sendPacket);
// buffer = new byte[BUFFER_SIZE];
Arrays.fill(buffer, (byte) 0);
receivePacket = new DatagramPacket(buffer, buffer.length);
}
outputStream.flush();
outputStream.close();
textArea.append("Received file successfully. Saved as " + fileName + "\n");
// Tell the client transmission is complete. Just send back the total number of bytes
// received.
sendPacket.setData(String.valueOf(totalBytesReceived).getBytes());
socket.send(sendPacket);
// Reset creation flag
createFile = true;
totalBytesReceived = 0;
// Wait for client to send another file
socket.receive(receivePacket);
}
} catch (IOException e) {
System.err.println(e);
}
}
