title: to use procedures from a class, when is the best time to extend a class vs. create an instance of that class?
body: <p>In Java, I created a class <code>CommonExcelFunctions</code> to store procedures I use across a couple projects.  there are no abstract procedures in the class.  To use these, I'm trying to decide if I should make my other projects extend this class, or if I should instantiate it and access them all through the instantiated object.  which way makes the most sense?  </p>