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POWhy is this socket null?
 

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    <p>I am creating a multi client chat server and i am pretty confident that it will work (Correct me if i'm wrong), I have the issue that on the socket that the client connects to is null so the connections can't be created because i use if(Socket != null) so i don't get errors but i will explain my layout real fast. The server starts with a starter class called (LaunchServer) that uses the class object ClientConnector as Minecraft and then starts the method runServer(). Here is the code for this class:</p> <pre><code>public class LaunchServer { public static void main(String[] args) { System.out.println("[Info] Running"); ClientConnector Minecraft = new ClientConnector(); Minecraft.runServer(); } } </code></pre> <p>It's fairly simple. This brings us to the ClientConnector class. Here we start at the method runServer(). Right away we have a try catch block. in that block we print a message that the server is trying to connect to the port 1337. we then create a new ServerSocket called serversocket. We then send a message to the console saying that we have bound to port and that we are awaiting a connection. While true, we create a new Socket socket that equals ServerSocket.accept(); OMG fuck it. Heres the code. you know what it does...</p> <pre><code>import java.util.ArrayList; import java.net.*; import java.io.*; public class ClientConnector { public static ArrayList&lt;Socket&gt; Connections = new ArrayList&lt;Socket&gt;(); public static void runServer() { try { System.out.println("[Info] Attempting to bind to port 1337."); @SuppressWarnings("resource") ServerSocket serversocket = new ServerSocket(1337); System.out.println("[Info] Bound to port 1337."); System.out.println("[Info] Waiting for client connections..."); while(true) { Socket socket = serversocket.accept(); new ClientHandler(socket).start(); Connections.add(socket); } } catch (IOException e) { e.printStackTrace(); } } } </code></pre> <p>This takes us to the handler class:</p> <pre><code>import java.io.*; import java.net.*; public class ClientHandler extends Thread { Socket Socket; public ClientHandler(Socket socket) { socket = Socket; System.out.println("[Info] Client connected on port 1337."); } public void run() { while(true) { for(int i = 0; i &lt; ClientConnector.Connections.size(); i++) { try { if(Socket != null)//This stays null... { ObjectOutputStream Output = new //These can't be created... ObjectOutputStream(Socket.getOutputStream()); ObjectInputStream Input = new ObjectInputStream(Socket.getInputStream()); whileChatting(Input, Output); } } catch (IOException e) { e.printStackTrace(); } } } } public static void sendMessage(String message, String returnedMessage, ObjectOutputStream out) { try { if(!message.isEmpty()) { out.writeObject("\247c[Server]\247d " + message); out.flush(); System.out.println("[Chat] Sent: " + message); } else { out.writeObject(returnedMessage); System.out.println("[Chat] Sent: " + returnedMessage); } out.flush(); System.out.println("[Info] Fluching remaining data to stream."); System.out.println("\n[Server] " + message); } catch(IOException ioException) { System.out.println("[Warning] Error: ioException @ sendMessage line 76."); } } public static void whileChatting(ObjectInputStream input, ObjectOutputStream output) throws IOException { String message = ""; do { try { message = (String) input.readObject(); System.out.println("\n" + message); sendMessage("", message, output); } catch(ClassNotFoundException classNotFoundException) { System.out.println("[Warning] Error: ClassNotFoundException @ whileChatting line 1-7."); System.out.println("\n idk wtf that user sent!"); } }while(!message.equals("/stop")); } } </code></pre> <p>Read the run method. There you will see the null problem</p> <p>Would the connection get accepted then passed to the hander class? How can a null connection get accepted? My question is how can i fix this problem?</p>
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    1. COThere is a typo in the variable name in class `ClientHandler` -- you have written `Socket Socket` , that is the cause of all errors. Look at the constructor, you have all messed up with variable names
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