Multi Client Server Chat Program In Java
Python socket chat server and client with code example. Socket based chat application. Socket based chat application In our previous article on we learned about the basics of creating a socket server and client in python. In this post we are. In our previous article on socket programming in python we learned about the basics of creating a socket server and client in python. In this post we are going to write a very simple chat application in python that is powered by sockets. The chat application we are going to make will be more like a chat room, rather than a peer to peer chat. So this means that multiple users can connect to the chat server and send their messages. Every message is broadcasted to every connected chat user. The construction is as simple as the theory. Code. The code consists of 2 python scripts. First is the server and the other is the chat client. Chat server. The chat server does the following things. Accept multiple incoming connections for client. Read incoming messages from each client and broadcast them to all other connected clients. Here is the code of the chat server. It server opens up port 5. The chat client must connect to this same port. You can change the port number if you want. The server handles multiple chat clients with select based multiplexing. The select function monitors all the client sockets and the master socket for readable activity. If any of the client socket is readable then it means that one of the chat client has send a message. Get the list sockets which are ready to be read through select. CONNECTIONLIST,. When the select function returns, the readsockets will be an array consisting of all socket descriptors that are readable. So if the master socket is readable, the server would accept the new connection. If any of the client socket is readable, the server would read the message, and broadcast it back to all clients except the one who send the message. The following function broadcasts the message to all chat clients. Do not send the message to master socket and the client who has send us the message. C Multi threaded Server Socket programming MultiThreaded Server Socket Program here is a C Console based application, that can handle multiple clients at the same. A list of Internetrelated terms and definitions. Flash-Chat-PHPBB-Chat-Module.jpg' alt='Multi Client Server Chat Program In Java' title='Multi Client Server Chat Program In Java' />CONNECTIONLIST. CONNECTIONLIST. removesocket. If the broadcast function fails to send message to any of the client, the client is assumed to be disconnected and the connection is closed and the socket is removed from the connection list. Rest of the program is quite self explanatory. Here is the full code of the chat client. Tcp Chat server. Function to broadcast chat messages to all connected clients. Do not send the message to master socket and the client who has send us the message. CONNECTIONLIST. if socket serversocket and socket sock. CONNECTIONLIST. removesocket. List to keep track of socket descriptors. CONNECTIONLIST. RECVBUFFER 4. Advisable to keep it as an exponent of 2. AFINET, socket. SOCKSTREAM. Upload_PSC/ScreenShots/PIC20031118851441555.JPG' alt='Multi Client Server Chat Program In Java' title='Multi Client Server Chat Program In Java' />SOLSOCKET, socket. SOREUSEADDR, 1. PORT. Img/20140422/20140422084015_961.png' alt='Multi Client Server Chat Program In Java' title='Multi Client Server Chat Program In Java' />JSR82 Java Bluetooth Articles, Tutorials and Discussion Forums about Java Bluetooth Programming and JSR82 Bluetooth API. Corporate home page with full range of product descriptions, Patrol and SiteAngel are the enterprise level monitoring products. Solidworks 2010 32 Bit Full Version Download. X11vnc a VNC server for real X displays to FAQ to Downloads to Building to Beta Test to Donations x11vnc allows one to view remotely. Add server socket to the list of readable connections. CONNECTIONLIST. appendserversocket. Chat server started on port strPORT. Get the list sockets which are ready to be read through select. CONNECTIONLIST,. New connection. Handle the case in which there is a new connection recieved through serversocket. CONNECTIONLIST. appendsockfd. Client s, s connected addr. Some incoming message from a client. Data recieved from client, process it. In Windows, sometimes when a TCP program closes abruptly. Connection reset by peer exception will be thrown. RECVBUFFER. broadcastdatasock, r lt strsock. Client s, s is offline addr. Client s, s is offline addr. CONNECTIONLIST. removesock. Run the server in a console. Chat server started on port 5. Chat client. Now lets code the chat client that will connect to the above chat server. The client is based on the telnet program in python. It connects to a remote server, sends messages and receives messages. The chat client does the following 2 things 1. Listen for incoming messages from the server. Check user input. If the user types in a message then send it to the server. Now here is something tricky. The client has to actually listen for server message and user input at the same time. To do this, we use the select function. The select function can monitor multiple sockets or file descriptors for some interesting activity which is this case is readable. When a message comes from the server on the connected socket, it is readable and when the user types a message and hits enter, the stdin stream is readable. So the select function has to monitor 2 streams. First is the socket that is connected to the remote webserver, and second is stdin or terminal input stream. The select function blocks till something happens. So after calling select, it will return only when either the server socket receives a message or the user enters a message. If nothing happens it keeps on waiting. Get the list sockets which are readable. We simply create an array of the stdin file descriptor that is available from the sys module, and the server socket s. Then we call the select function passing it the list. The select function returns a list of arrays that are readable, writable or had an error. The readable sockets will be again a list of sockets that is readable. So in this case, the readsockets array will contain either the server socket, or stdin or both. Then the next task is to do relevant processing based on which socket is readable. If the server socket is readable, it means that the server has send a message on that socket and so it should be printed. If stdin is readable, it means that the user typed a message and hit enter key, so that message should be read and send to server as a chat message. Here is the python code that implements the above logic using select function telnet program example. You. sys. stdout. Usage python telnet. AFINET, socket. SOCKSTREAM. Unable to connect. Connected to remote host. Start sending messages. Get the list sockets which are readable. Disconnected from chat server. Run the client from multiple consoles. Connected to remote host. Start sending messages. You hello. lt You I am fine. You on another consolelt You 1. I am fine. lt You ok good. So the messages send by one client are seen on the consoles of other clients. Logic is quite simple. Run it and check it out. Note. The above shown chat client is not going to work on windows. It uses the select function to read data from both the socket and the input stream. This works on linux but not on windows. The python documentation on select mentions this. File objects on Windows are not acceptable, but sockets are. On Windows, the underlying select function is provided by the Win. Sock library, and does not handle file descriptors that dont originate from Win. Sock. Linux treats sockets and file descriptors in the same manner, therefor the select function is able to read from stdin. On windows the select function will not read anything except sockets created by the winsock socket functions. There is another drawback that the above shown chat program suffers. If in the chat client a user is typing a message and while typing a message comes from the server, then the server message shall be printed rightaway and the message that the user was typing would be lost. That is the expected behaviour of this program and there is nothing that can be done to fix this properly. Only solution is to use better terminal libraries like ncurses to keep the user input separate from terminal output. Or write a gui program. Last Updated On 2.