There is a difference between knowing something and implementing it.
I have been well versed in the SOLID principles, on top of that I have given short presentations on them. However, sometimes it may be difficult to implement those ideas into your code.
I faced such an issue today.
I had been having my RequestHandlerdo many duties. Before I refactored it was 162 lines of code. Originally it was meant to guide the send the requests to their desired handling.
Then I decided to handle the requests there as well.
This violates the Single Responsibility principle, the Open-Closed principle, and the Dependency Inversion principle.
SRP because clearly the class was doing multiple things.
OCP because I could not have added new features without going in and doing extensive code surgery.
And finally DIP specifically because I am trying to implement the Guessing game as one of the pathways.
I have a guessing game, and I wanted to connect it directly to this RequestHandler class. However, I was creating a method in the RequestHandler class and it was getting very large. This meant that the RequestHandler was dependent on the details of the Guessing game.
Why does the RequestHandler care about the details of the Guessing Game? It shouldn’t, it should care that it can send the request to the correct location and that is it!
So now I have cleaned up the Class and it is now only 64 lines long, and I created 3 more classes to handle their desired locations!
Now my main method in RequestHandler looks like this:
private Response handleDirectories(Request request) {
String requestPath = request.getPath();
switch (requestPath) {
case "/hello":
return FilePathHandler.generateResponse("Hello",
"<h1>Hello!</h1><p>Welcome to My Server!</p>");
case "/favicon.ico":
return keepPath;
case "/ping":
return ping.handlePing();
case "/guess":
Response guessingGame = guessingGameHandler.handleGuess(request);
return guessingGame;
default:
return handleDefaultPath(requestPath);
}
}
Nice and simple.
Until next time!
Merl