When should you use getters and setters? Getters and setters are great for configuring or determining the configuration of a class, or retrieving data from a model Getting the price of an item is an entirely reasonable use of a getter. That is data that needs to be available and may involve special considerations to … Read more
Encapsulation helps in isolating implementation details from the behavior exposed to clients of a class (other classes/functions that are using this class), and gives you more control over coupling in your code. Consider this example, similar to the one in Robert Martin’s book Clean Code: public class Car { //… public float GetFuelPercentage() { /* … Read more
From here: Adapter provides a different interface to its subject. Proxy provides the same interface. You might think of an Adapter as something that should make one thing fit to another that is incompatible if connected directly. When you travel abroad, for example, and need an electrical outlet adapter. Now a Proxy is an object … Read more
I tend to add a Base suffix to the name of the base class only if it exists from technical perspective (to share some code), and doesn’t really constitute any usable class on its own (so all of these classes are abstract). These are quite rare cases though, and should be avoided just as Helper … Read more
Polymorphism can be achieved through overriding. Put in short words, polymorphism refers to the ability of an object to provide different behaviors (use different implementations) depending on its own nature. Specifically, depending on its position in the class hierarchy. Method Overriding is when a method defined in a superclass or interface is re-defined by one … Read more
A local variable is the variable you declare in a function. A member variable is the variable you declare in a class definiton.
Wow, I happened to visit this thread exactly one year after I posted my last answer here. 🙂 Scala 2.9.1. mutable.Map comes with a withDefaultValue method. REPL session: scala> import collection.mutable import collection.mutable scala> mutable.Map[Int, String]().withDefaultValue(“”) res18: scala.collection.mutable.Map[Int,String] = Map() scala> res18(3) res19: String = “”
Idiomatic Clojure favors defining independent functions that operate on a very small set of core data structures; this unbundling of methods and data is a strong statement against object orientation and in favour of a functional style. Rich Hickey (creator of Clojure) has repeatedly stated the importance of this; for example here: “Clojure eschews the … Read more
The best thing you can do is: Have a ton of Q&A. Wikipedia’s procedural programming (PP) article really hits where you should start: Whereas procedural programming uses procedures to operate on data structures, object-oriented programming bundles the two together so an “object” operates on its “own” data structure. Once this is understood, I think a … Read more
In addition to the answers already given, here’s a link to an article I think is relevant. Excerpts: In the object-oriented framework, inheritance is usually presented as a feature that goes hand in hand with subtyping when one organizes abstract datatypes in a hierarchy of classes. However, the two are orthogonal ideas. Subtyping refers to … Read more