Monday, May 13, 2013
Good software design principle part 4
Another thing that was a big success in the SMF was the use of List and Map(s) (Dictionary in .net). If a class looks like a List, smells like a List and sounds like a list then it probably is a List. This might sound trivial but I have seen project where a class with getters and setters was defined to handle a concept that obviously was a Map. People had to constantly update the interface when new properties where added and the whole thing really was a nightmare. Using data structures such as Lists and Maps makes programming in Java feel much more like dynamic programming. So the IInstrumentDefinition includes a number of methods that actually return unmodifiable Maps. The Maps are generic Map<String, INamedParameter> where the INamedParameter interface is a little one element heterogeneous container. The INamedParameter defines the name, class and value of a parameter or variable. A Map of those is a nice little package that can easily give access to the List<String> of INamedParameter names. Once you have the name you can get the actual INamedParameter from the Map.