Chat server and a chat client, utilizing Threading, TCP Sockets, handling of raw binary data and more.

The server and client communicate with messages. Each message a (binary) string with the following structure:

1.First 8 bytes are always 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0xEF, 0xDE, 0xAD

2.Messages are encoded with a TYPE-LENGTH-BODY (TLB) scheme: A single byte for TYPE, 4 big-endian bytes for LENGTH, and LENGTH bytes for BODY). For simplicity, the body is always a string, even when the body is a number.

Message Codes:

0x00 -Client Keep-alive. No body.

0x01 -Client Connect. Body =

0x02 -Client Disconnect. Body =

0x03 -Client Public Message. Body = \n

0x04 -Client Private Message. Body = \n\n

0x10 -Server ACK for Client Keepalive. Body = String containing seconds since last KA received for this client.

0x11 -Server ACK for Client Connect. Body = String containing CSV of all available client names.

0x12 -Server ACK for Message Enqueued. Body =

0x13 -Server announcement of a party who has joined. Body =

0x14 -Server announcement of a party who has left. Body =

0x15 -Server announcement of a new message. Body = \n

0x20 -Server Error – Received a message from an un-registered client

0x21 -Server Error – Cannot deliver message to client X (unregistered)

0x22 -Server Error – Cannot register client – already registered.

0xEE -General Client Error. Body=Error description (stack trace?)

0xFF -General Server Error. Body=Error description (stack trace?)