digitsisyph/java_commandline_chatroom

Java_CommandLine_Chatroom

To run the program:

# 1. complie all java codes
javac */*.java javac *.java

# 2. run the Server
# java Server [port] [block_duration] [time_out] 
java Server 2050 30 30

# 3. run the Client
# java Client [server_ip_address] [port] 
java Client localhost 2050

System Description

• Server: After being started, the server would first create a server socket, which waits for a connection from a client.
  • When it receives a new connection, the server would create a new thread ServerConnection in charge of this new connection.
  • The thread would authenticate the client first. After authenticating, the client can send their commands and the thread would respond correspondingly.
• Client: After being started, the client would start three threads:
  1. UserThread: in charge of dealing with the user input and send it to the server
  2. ServerThread: in charge of dealing with the client input and display it to the user
  3. P2PThread: in charge of dealing with the peer input or output and display it to the user

Application Layer Message Design

To keep messages between the server and clients as simple as possible, there are only few kinds of message formats:

• From server to client:
  1. youare [username]: this message is used to set the username of the client after auth.
  2. p2p [username] [ip_address] [port]: this message is used to transfer the peer-to- peer information of another client.
  3. close: this message is used to close the client.
  4. text (Default): other messages would be displayed directly.
• From client to server: the client would send user commands directly to the client.
• From client to another client (peer-to-peer):
  1. thisis [username]: this message is used to inform the peer client the username.
  2. stopprivate [username]: this message is used to inform the peer client stop the connection with the user.
  3. text (Default): other messages would be displayed directly.