/**
* openConnections: open the connection to the master. has retry mechanism
*
* @return: true if the connection is built, false if failed
*/
public boolean openConnections() {
_log("Try to connect to Master...");
int i = 0;
while (true) {
boolean isConnected = connect();
if (!isConnected) {
i++;
if (i == DropboxConstants.MAX_TRY) {
break;
}
_log("Cannot connect to Master, retry " + i);
try {
Thread.sleep(DropboxConstants.TRY_CONNECT_MILLIS);
} catch (InterruptedException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
_log("Retry connection is interrupted");
break;
}
} else {
_log("Success!");
return true;
}
}
_log("Failed");
return false;
}
/**
* sendUserID: send id to the user print writer
*
* @return: the response
*/
protected String sendUserID() throws Exception {
assert _userOut != null;
String output = ProtocolConstants.PACK_STR_USR_HEAD + " " + _server.getID();
String reply = NetComm.sendAndRecv(output, _userOut, _userIn);
return reply;
}
/**
* sendAll: send all of the information to the print writer
*
* @return: the response
*/
protected String sendAll() throws Exception {
assert _out != null;
String output = _server.getID() + " " + _server.getPrio() + " " + _server.getMaxClientNum();
Map<String, ClientNode> mp = _server.getClients();
Iterator it = mp.entrySet().iterator();
while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next();
String name = (String) pair.getKey();
ClientNode node = (ClientNode) pair.getValue();
output += " " + name + " " + node.getPassword();
}
output = ProtocolConstants.PACK_STR_ID_HEAD + " " + output;
String reply = NetComm.sendAndRecv(output, _out, _in);
return reply;
}
/**
* parse: parse the string and send response
*
* @param str: the given string
*/
protected void parse(String str) {
StringTokenizer st = new StringTokenizer(str);
String tkn = st.nextToken();
try {
if (tkn.equals(ProtocolConstants.PACK_STR_HEARTBEAT_HEAD)) {
_dlog("I got heartbeat");
// Send back confirmation
// TODO: add more story here
NetComm.send(ProtocolConstants.PACK_STR_HEARTBEAT_HEAD, _out);
} else if (tkn.equals(ProtocolConstants.PACK_STR_REQUEST_FS_HEAD)) {
// TODO: add more story here
} else {
_elog("Invalid header, skip.");
}
} catch (Exception e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
}
}
/** listen: start to listen if there is any clients connected */
public void listen() {
// Firstly spawn a new thread and then the main thread
// also start listening
_userNet = new DropboxFileServerUserNet(_server, _userOut, _userIn, _userSock);
_userNet.start();
/* Use main thread, cannot be stopped */
while (_sock != null && !_sock.isClosed()) {
try {
String line = NetComm.receive(_in);
_dlog(line);
parse(line);
} catch (Exception e) {
if (!_server.noException()) {
_elog(e.toString());
}
break;
// Break the loop
}
}
/* Clear */
// Close main thread
clear();
// Cancel the listening thread and retry
_server.cancelListeningThread();
/* Also cancel all of the syncers */
_server.cancelSyncers();
// Retry after
try {
_log(
"The connection to master is broken,"
+ " reset everything and retry connection after "
+ DropboxConstants.TRY_CONNECT_MILLIS
+ " milliseconds");
Thread.sleep(DropboxConstants.TRY_CONNECT_MILLIS);
} catch (InterruptedException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
}
_server.run();
clear();
_log(_threadName + " is stopped");
}
/**
* close: close the socket and stream
*
* @return: true for success, false for error
*/
protected boolean close() {
_dlog("Do main thread closing...");
if (_sock != null && !_sock.isClosed()) {
_dlog("Closing the receiving thread");
try {
_sock.close();
_in.close();
_out.close();
_sock = null;
_in = null;
_out = null;
_dlog("Success!");
} catch (IOException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
return false;
}
}
_sock = null;
_in = null;
_out = null;
_dlog("Cancel the user input thread");
if (_userNet != null) {
_userNet.stop();
_userNet.join(); // guaranteed to be closed
_userNet = null;
}
if (_userSock != null && !_userSock.isClosed()) {
_dlog("Closing the user input thread");
// Stop the user thread
try {
_userSock.close();
_userIn.close();
_userOut.close();
_userSock = null;
_userIn = null;
_userOut = null;
_dlog("Success!");
} catch (IOException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
return false;
}
}
_userSock = null;
_userIn = null;
_userOut = null;
/* Cancel all client nodes */
_dlog("Finished");
return true;
/* CAUTION: _server is never cleared */
}
private void _dlog(String str) {
if (_server.debugMode()) System.out.println("[DropboxFileServerMasterNet (DEBUG)]:" + str);
}
/**
* connect: connect to the master
*
* @return: true for success and false for failure
*/
protected boolean connect() {
boolean connected = true;
try {
_sock = new Socket(_serverIP, _serverPort);
_out = new PrintWriter(_sock.getOutputStream(), true);
_in = new BufferedReader(new InputStreamReader(_sock.getInputStream()));
String reply = sendAll();
if (!reply.equals(ProtocolConstants.PACK_STR_CONFIRM_HEAD)) {
/* Tokenize */
StringTokenizer st = new StringTokenizer(reply);
if (st.nextToken().equals(ProtocolConstants.PACK_STR_ERRMES_HEAD)) {
_elog(st.nextToken());
return false;
}
}
_userSock = new Socket(_serverIP, _serverPort);
_userOut = new PrintWriter(_userSock.getOutputStream(), true);
_userIn = new BufferedReader(new InputStreamReader(_userSock.getInputStream()));
String replyUser = sendUserID();
if (!replyUser.equals(ProtocolConstants.PACK_STR_CONFIRM_HEAD)) {
throw new Exception("Not confirmed");
}
} catch (UnknownHostException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
connected = false;
} catch (IOException e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
connected = false;
} catch (Exception e) {
if (!_server.noException()) {
_elog(e.toString());
}
if (_server.debugMode()) {
e.printStackTrace();
}
connected = false;
}
if (!connected) {
return connected;
}
if (!connected) {
/* Remove the pair of socket */
_sock = null;
_in = null;
_out = null;
_userSock = null;
_userOut = null;
_userIn = null;
}
return connected;
}