WebServer - a minimal web server implementation

To run the server, run in the project root directory: java -cp WebServer.jar webserver.WebServer

The implementation consists of the 'webserver' package and the following classes:

i. WebServer - the entry point, where the 'main' method is situated. It starts the server thread and also ends it gracefully when the input "exit" is introduced at System.in.

ii. Server - which implements Runnable, is a thread running the server logic, opening a socket that accepts connection from clients and instantiates them on a new thread in idle state from the thread pool.

iii. Connection - also implements Runnable and runs the connection logic. Inside it, the input stream is sent to be parsed, the operations resulted are sent to be applied and the response is sent to be parsed also and then written to the output stream.

iv. HTTPParser - is the class where the request is parsed and relevant data (for the minimal implementation) is stored in a Map and the Map which stores the response data is parsed to a string and then converted to a byte array.

v. Helper - is the class where the logic of the operations (creating, reading, writing, deleting files) is implemented and also, the response Map of data is filled in.

The capabilities of the web server implemented by this project are:

1. The connection is closed by the server after sending the response.

2. In case of a File Not Found error, Bad Request error, Forbidden error or Internal Server error, specific pages existent in 'www/html/error_pages' are sent as response.

3. The HTTP response header consists of the line, date line, server line, connection closed line and optional allow method line and content-type/length lines.

4. Method supported are: i) GET - returns the requested resource content ii) HEAD - returns the header of a supposed GET request iii) POST - creates the requested resource or overwrites an existent one and returns its content iv) PUT - overwrites the requested resource and returns its content v) PATCH - append data to the requested resource and returns its content vi) DELETE - deletes the requested resource and returns no content vii) OPTIONS - adds the Allow header and returns no content

Important: POST, PUT, PATCH requests with no data will behave as a GET request.