code: public <T extends IGeneratorParameter<S>, S> S getDefault(Class<T> param) {
          if (renderingParameters.containsKey(param.getName())) return getParameter(param).getDefault();
  
          // OK, this parameter is not registered, but that's fine, as we are
          // only to return the default value anyway...
          try {
              return param.newInstance().getDefault();
          } catch (InstantiationException exception) {
              throw new IllegalArgumentException("Could not instantiate a default " + param.getClass().getName(),
                      exception);
          } catch (IllegalAccessException exception) {
              throw new IllegalArgumentException("Could not instantiate a default " + param.getClass().getName(),
                      exception);
          }
      }
docs: Returns the default value for the {@link IGeneratorParameter} for the
  active {@link IRenderer}.
  
  @param param {@link IGeneratorParameter} to get the value of.
  @return the default value for which the type is defined by the provided
  {@link IGeneratorParameter}-typed <code>param</code> parameter.
  
  @see #get(Class)