java - unable to send messages on chat program -

i writing chat program in java. can't seem able send messages. clientconnectionhandler handles instance of each client

import java.io.*; import java.net.*; import java.text.*; import java.util.*;   public class clientconnectionhandler extends thread {    private socket socket; string username; private uuid id; //= uuid.randomuuid(); bufferedreader reader; printwriter writer; private final hashmap<uuid, clientconnectionhandler> clients = new hashmap<>(); volatile boolean messageloop = true;  servergui servergui;  public clientconnectionhandler(socket socket){     this.socket = socket;     try{         this.socket.setsotimeout(1000);      }      catch (socketexception e) {          system.out.println(e);     }      try {          reader = new bufferedreader(new inputstreamreader(socket.getinputstream()));         writer = new printwriter(new outputstreamwriter(socket.getoutputstream()));     }     catch (exception e){         e.printstacktrace();     } }  public void run(){     if (socket != null && reader != null) {         addtoclients();         try {             string messageinput;             while (messageloop){                 try{                     messageinput = reader.readline();                     sendmessage(messageinput);                   }                 catch(sockettimeoutexception ste){                     //thread.yield();                 }             }         }         catch (ioexception e){             e.printstacktrace();         }         {             removefromclients();             try {                 reader.close();                 writer.close();             }             catch (ioexception e) {                 e.printstacktrace();             }          }     }      else {         system.out.println("socket connection , bufferedreader closed");     } } private void sendmessage(string msg){     (clientconnectionhandler cchandler : clients.values()){         try {             //if (!clientconn.id.equals(this.id)) {                 cchandler.writer.write(msg+"\n");                 cchandler.writer.flush();             //}         }         catch (exception e){             system.err.println("unable write client");             clients.remove(cchandler.id);         }     } }  } 

here's client class

public class client {     private socket clientsocket;     private string username;     private static int port = 7777;     bufferedreader inreader;     printwriter outwriter;     private simpledateformat sdf;     clientgui clientgui;     servergui servergui;     private login login;      public client(string username, int port){         this.username = username;         this.port = port;         sdf = new simpledateformat("dd.mm.yyyy 'at' hh:mm:ss a");        }      /**      * connects client server      */     public void connectclient(){         try{             clientsocket = new socket("127.0.0.1", port);             thread thread = new thread(new clientconnectionhandler(clientsocket));             thread.start();             string connected = sdf.format(new date())+"\n"+username+" connected \n";             system.out.println(connected);         }         catch(exception e){              system.out.println(sdf.format(new date())+"\n"+username+" did not connect server "+e+"\n");         }            }      /**      * disconnects client server      */     void disconnectclient(){         try{             clientsocket.close();             system.out.println(username+" disconnected \n");         }         catch(exception e){             system.out.println(username+" failed disconnect \n");         }     }       //send message server     public void sendmessage() throws ioexception{         try{             inreader = new bufferedreader(new inputstreamreader(clientsocket.getinputstream()));             outwriter = new printwriter(new outputstreamwriter(clientsocket.getoutputstream()));         }         catch(ioexception ioe){          }          //infinite loop check messages         try{             string response;             string inputmsg = inreader.readline();             outwriter.println(inputmsg);                 while((response = inreader.readline()) != null){                 system.out.println(response);                 outwriter.println(inputmsg);             }             inreader.close();             outwriter.close();             //clientgui.appendmessage(inputmsg);         }         catch(ioexception ioe){          }     }      void appendtocg(string str){         clientgui.appendmessage(str);     }      public static void main(string[] args) {         client client = new client("127.0.0.1",port);     }  } 

edit

startserverconnection() method in server class:

public void startserverconnection()      {          try {              serversocket = new serversocket(portnumber);               while(connection){                 system.out.println("waiting client...");                  socket clientsocket = serversocket.accept();                  system.out.println("server connection established on port: "+clientsocket.getlocalport());                  clientconnectionhandler clientconnection = new clientconnectionhandler(clientsocket);                  thread thread = new thread(clientconnection);                  thread.start();              }         }          catch (exception e) {              // system.out.println(sdf.format(new              // date())+": server didn't connect"); //append eventslog              e.printstacktrace();              return;          }      } 

i'm pretty sure i've created readers , writers necessary, on both clientconnectionhandler (for each user send message) , client read messages. missing out on something?

probably not full resolution, but:

1. the clientconnectionhandler extends thread. should extend runnable since create thread in startserverconnection().

2. it looks attempting reuse clientconnectionhandler between server , client. approach may not want. more want different runnable client. haven't thought through of implications, might able make client class implement runnable, , change client

   public void connectclient(){ try{     clientsocket = new socket("127.0.0.1", port);     // set timeout here, or block io! alternatively,     // use nio stuff     thread thread = new thread(this);     thread.start();     string connected = sdf.format(new date())+"\n"+username+" connected \n";     system.out.println(connected); } catch(exception e){      system.out.println(sdf.format(new date())+"\n"+username+" did not connect server "+e+"\n"); }        }  public void run() {     try {       clientsocket.setsotimeout(1000);        //loop read messages sent *this* client       while (true) {         try {             string inputmsg = reader.readline();             // print stdout; might want update gui             system.out.println(inputmsg);         }         catch (sockettimeoutexception noop) { }       } //end of while loop      }      catch (exception e) {        // note error may not problem since        // disconnect client close socket,        // cause error @ future point.        system.err.println(e);      }      } } 

3. in client.sendmessage() method:
   a. message want send? must gathering input somewhere
   b. not attach , close streams in method.

4. so presumably in client class need like:

   public void sendmessage() throws ioexception{   try{      // message send somewhere      string msgtosend = "foo";  // dumb text; replace actual      writer.write(msgtosend);      writer.write("\n");  // needed      writer.flush();  // flush buffer   }  }