The virtual cafe is a multithreaded cafe that serves tea and coffee to customers, clients can join the cafe server, order tea and coffee, check the status of their orders and collect their items.
The cafe logs the events to the terminal and a json file.
This project requires a Java Development Kit to compile and run.
Gson
To compile the project run
javac -cp ".:gson.jar" Barista.java
javac -cp ".:gson.jar" Customer.java
To run the compiled files run the following commands.
Server program command.
java -cp ".:gson.jar" Barista
Client program command.
java -cp ".:gson.jar" Customer
You could utilize netcat or the nc command on linux to represent the client or the server.
The server runs on port 8080 by default so an alternative to server run is.
nc -l 0.0.0.0 8080
for the client
nc 0.0.0.0 8080
Through the customer interface you can utilize keywords like
- order
- status
- collect
- exit
The order keyword should be trailed with information about the specific order like "4 teas and 4 coffees" or "1 tea".
status shows the client their order status in the format.
status example
- 1 tea and 2 coffees in waiting area
- 2 teas and 2 coffees currently being prepared
- 2 teas in tray
collect retrieves the users order.
exit leaves the cafe.
If you are connecting at a socket using netcat you will have to input requests the exact using the format as the ones below.
The server and client use json to communicate The json is formed of a request type and the data it contains. Using the request type the client and server know exactly what to do with the data provided.
example json requests
{ "type": "JOIN", "data": { "name": "syrup" } }{"type":"ORDER","data":{"items":{"tea":3,"coffee":1}}}- JOIN
- LEAVE
- EXIT
- ORDER
- STATUS
- COLLECT
- MESSAGE
- TERMINATE
- ERROR
Join: This requires a data property called name containing a string value.
Order: This requires a data property called items containing tea and coffee with their respective counts.
Message or Error: This requires a data property called message containing a string.
The server utilizing multiple threads to run the cafe and handle client orders.
The server and clients can be hosted on different processes and communicate via TCP sockets.
The program can handle users with the same name by generating and using a unique user id under the hood.
The program has shutdown hooks that it can use to
While it can transfer brewing items from one client to another, currently the program cannot transfer orders in a clients tray from to another.
It loads the orders sequentially which can result in some delay in order confirmation for extremely high quantities.
The server program was built using the Customer program as a standard, when using netcat or sending malformed json requests through other means the server might falter.