I have a some sort similar problem to this, but I've I am aware that when I ask to read a line, the the sender should send an end-of-line.
What confuses me, is that in debugging, it works. Probably because the order I step over on debug (which I didn't even knew that could make a difference until now), but I want to understand it better.
I already worked with threads, but not very much.
Here is my Server class:
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
public class Server {
protected static List<Game> games = new ArrayList<>();
protected static List<ServerThread> players = new ArrayList<>();
public static void main(String[] args) throws Exception {
int serverPort = 8945;
Server server = new Server();
ServerSocket welcomeSocket = new ServerSocket(serverPort);
while (true) {
Socket connectionSocket = welcomeSocket.accept();
ServerThread st = new ServerThread(server,connectionSocket);
st.start();
int gameId = 0;
if(players.size()>0 && players.size()%2==0){
gameId++;
players.get(0).outToClient.write("START " + gameId
+ " 123 456" +"\n");
players.get(0).outToClient.flush();
players.get(1).outToClient.write("START " + gameId
+ " 456 123" +"\n");
players.get(1).outToClient.flush();
}
}
}
}
The Thread (based on this)
import java.io.*;
import java.net.Socket;
public class ServerThread extends Thread {
protected Server server;
protected Socket socket;
protected String playerName;
protected BufferedReader inFromClient;
protected BufferedWriter outToClient;
public ServerThread(Server server, Socket clientSocket) throws IOException {
this.server = server;
this.socket = clientSocket;
this.inFromClient = new BufferedReader(new InputStreamReader(socket.getInputStream()));
this.outToClient = new BufferedWriter(new InputStreamReader(socket.getOutputStream()));
}
public void run() {
while (true) {
try {
String line = inFromClient.readLine();
if(line != null) {
String[] clientCommand = line.split(" ");
String commandType = clientCommand[0];
if (!commandType.equalsIgnoreCase("QUIT")) {
switch (commandType) {
case "JOIN":
playerName = clientCommand[1];
System.out.println(playerName + " joined");
Server.players.add(this);
break;
case "PLAY":
//nothing yet
break;
case "MSG":
//nothing yet
break;
}
}
}
} catch (IOException e) {
e.printStackTrace();
return;
}
}
}
And the Client:
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.Socket;
public class Client {
private static int gameID;
private static int order;
private static String opponent;
public static void main(String[] args) throws Exception {
if (args.length != 1) {
System.out.println("Usage: java Client <serverIp>");
System.exit(1);
}
String serverIP = args[0];
int serverPort = 8945;
BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
Socket clientSocket = new Socket(serverIP, serverPort);
BufferedWriter outToServer = new OutputStreamWriter(clientSocket.getOutputStream());
BufferedReader inFromServer = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String line = inFromUser.readLine();
String[] commandSentence = line.split(" ");
String userCommandType = commandSentence[0];
while (!userCommandType.equals("/exit")){
switch (userCommandType){
case "/enter":
String nickname = commandSentence[1];
outToServer.write("JOIN "+ nickname + '\n');
outToServer.flush();
while (true){
String serverLine = inFromServer.readLine();
String[] serverCommand = serverLine.split(" ");
String serverCommandType = serverCommand[0];
if(serverCommandType.equalsIgnoreCase("START")){
gameID = Integer.parseInt(serverCommand[1]);
order = Integer.parseInt(serverCommand[2]);
opponent = serverCommand[3];
System.out.printf("%5s %5s %5s",gameID,order,opponent);
break;
}
}
case "/play":
//nothing yet
break;
case "/msg":
//nothing yet
break;
}
}
}
}
It looks like it enter a deadlock somewhere, and for some reason, never enter that if on Serverclass which send data to the clients, unless running in debug
(BTW, I am using get(0) and get(1) like that for test purposes only)
EDIT: Ok, my silly mistake is that I forget to add outToServer.flush(); when the Client is sending data to Server. But my main problem persist, when I create two clients by typing "/enter <nickname>" to each one, when the last one is added to the list, it is expected to enter that if statement on Server.
