I'm using Java Socket to send a file to server and then get a response back. The problem is every time i try to read the response from server, it makes the file-reading part of the server hang. I really need your help on what's going on here?
Here is SERVER code:
ServerSocket server = new ServerSocket(PORT);
Socket client = server.accept();
BufferedInputStream netInStream = new BufferedInputStream(client.getInputStream());
BufferedOutputStream netOutStream = new BufferedOutputStream(client.getOutputStream());
String outFileName = "output/test";
File outputFile = new File(outFileName);
if (!outputFile.exists()) {
outputFile.getParentFile().mkdirs();
}
FileOutputStream fileOutStream = new FileOutputStream(outputFile);
BufferedOutputStream bufOutStream = new BufferedOutputStream(fileOutStream);
// read file from client and save
int bytesRead = 0;
byte[] buffer = new byte[1024];
while ((bytesRead = netInStream.read(buffer)) > 0) {
bufOutStream.write(buffer, 0, bytesRead);
bufOutStream.flush();
Log.line("Bytes read: " + bytesRead);
}
// clean up file IO
// ...
// send response to client
netOutStream.write("File received by server".getBytes());
netOutStream.flush();
// clean up network IO
// ...
CLIENT code:
Socket client = new Socket(DOMAIN_SERVER, PORT_SERVER);
BufferedOutputStream netOutStream = new BufferedOutputStream(client.getOutputStream());
BufferedInputStream netInStream = new BufferedInputStream(client.getInputStream());
String inFileName = "input/test";
File file = new File(inFileName);
if (!file.exists()) {
client.close();
return;
}
FileInputStream fileInSream = new FileInputStream(file);
BufferedInputStream bufInStream = new BufferedInputStream(fileInSream);
// read and send file to server
int bytesRead = 0;
byte[] buffer = new byte[1024];
while ((bytesRead = bufInStream.read(buffer)) > 0) {
netOutStream.write(buffer, 0, bytesRead);
netOutStream.flush();
Log.line("Bytes sent: " + bytesRead);
}
// clean up file IO
// ...
// read response from server
StringBuilder res = new StringBuilder();
byte[] charBuf = new byte[128];
int msgBytesRead = 0;
while ((msgBytesRead = netInStream.read(charBuf)) > 0) {
res.append(new String(charBuf, 0, msgBytesRead));
}
Log.line(res.toString());
// clean up network IO
// ...
The flow is, client sends a file to server, server reads the file and saves to its local storage then the server sends a response string to client, the client reads the response and prints it out on the screen.
If the code is like above, the server will not exit the while-loop and hang, therefor the client second while-loop doesn't read anything and hang, too. But if i comment/remove the client second while-loop, both programs run and no hang occurs. File transfer is also success.
