code: protected void evalBase(final String _baseName)
      {
          final FilterBase baseTmp = EnumUtils.getEnum(FilterBase.class, _baseName.toUpperCase());
          if (baseTmp != null) {
              this.base = baseTmp;
          }
          activate();
      }
docs: Setter method for instance variable {@link #base}.
  
  @param _baseName value for instance variable {@link #base}