Polymorphism enables code to be more abstract. When your code references an interface instead of a class, it loses its coupling to that class and becomes more flexible in the face of future modifications. This use of abstraction was central to many of the techniques of the previous chapters.
Class constructors are the one place where such abstraction is not possible. If you want to create an object, you need to call a constructor; and calling a constructor is not possible without knowing the name of the class. This chapter addresses that problem by examining the techniques of object caching ...
