code: public static Sham getInstance() {
          if(Sham.instance == null) {
              Sham.instance = new Sham();
          }
          return Sham.instance;
      }
docs: Returns the global <code>Sham</code> instance. If one has not been explicitly set,
  a new instance is created and saved first, then returned.
  
  @return a previously saved static <code>Sham</code> instance, or a new one if not requested before