Here is a problem I’ve struggled with ever since I first started learning object-oriented programming: how should one implement a logger in ‘proper’ OOP code?
By this, I mean an object that has a method that we want every other object in the code to be able to access; this method would output to console/file/whatever, which we would use for logging–hence, this object would be the logger object.
We don’t want to establish the logger object as a global variable, because global variables are bad, right? But we also don’t want to have the pass the logger object in the parameters of every single method we call in every single object.
In college, when I brought this up to the professor, he couldn’t actually give me an answer. I realize that there are actually packages (for say, Java) that might implement this functionality. What I am ultimately looking for, though, is the knowledge of how to properly and in the OOP way implement this myself.
You do want to establish the logger as a global variable, because global variables are not bad. At least, they aren’t inherently bad. A logger is a great example of the proper use of a globally accessible object. Read about the Singleton design pattern if you want more information.