A Java developer must also be able to think and code ... programming, where an imperative function might be associated with state (such as a Java instance variable). Calling this function at ...

it requires access to the Java code in symbolic form. Such access currently is limited to the use of non-standard APIs or to conventions at different points in the program’s life cycle ...

This makes the class extensible to an infinite number of Shape classes that could potentially be created. Furthermore, the OpenClosedExample supports all of these new classes with no edits to the ...