code: protected CommandContext prepareContext(Object pmb) {
          final Object filteredPmb = filterPmb(pmb);
          final String[] argNames = new String[] { "pmb" };
          final Class<?>[] argTypes = new Class<?>[] { filteredPmb.getClass() };
          final CommandContextCreator creator = newCommandContextCreator(argNames, argTypes);
          return creator.createCommandContext(new Object[] { filteredPmb });
      }
docs: ===============