Posts Tagged ‘clojure’
Have you heard of mastermind? It’s a logic game in which one player repeatedly tries determine the secret code that another player set at the beginning. With each guess, the player is given information on how many correct pegs his guess contains, and how many are in the correct position. For more details on the rules, check the wikipedia article.
I built a Clojure implementation of Mastermind as a learning project. (Code and details of functionality at github.) My primary goals were to gain familiarity with the language, and to see what the functional programming paradigm feels like when working on a project that is larger than one big function. After I finished, I re-implemented (almost) all of the features in Java for a comparison. (Code also available at github.) Interested in the results? read on.
Sometimes you need to pass around a function. In Java, since “Everything Is An Object”, you make a class, and define the function as a method in that class. Of course, you need a separate source files for this, since you want this class to be public.
Before long, you find that in a different situation, you want to pass a different function, so you make an interface, another class, and make both classes extend the interface. Now the two functions that would have logically fit in some already existing file have generated three source files.
Does it have to be this way? It’s a lesser known fact that in Python, everything is an object. A function is an object, a class is an object, a module is an object. But somehow, a commitment to everything being an object didn’t lead Guido to conclude that everything should have it’s own class file. Somehow “Everything Is An Object” doesn’t imply (in Python or Ruby) that functions must be defined in classes.
I’ve been using Spring with Java, and that is certainly preferable to me than Java without Spring, for medium or large projects. But it strikes me that much of what Spring helps me manage is the simple fact that I need many functions available in situations where I don’t want to instantiate an object first. When I use Spring to inject a singleton object, often what I really want is a handful of related, stateless functions. I would guess that about well over half of the classes in my projects are essentially one of two things: glorified namespaces or data types without behavior.
More to the point, as I build complex applications, I fear that building them in Java significantly adds to the complexity. I fear that I’m building in a way that requires some acclimation to a handful of patterns and a framework that ultimately shift the complexity of the problem to a different sort of complexity. It seems that this is the best that the Java world allows: familiar patterns of complexity.
So what’s a Java developer to do? Where to go from here? Read the rest of this entry »