docs: public static String setOrAppend(final String target, final String value, final boolean withSpace) {
          if (target == null) {
              return value;
          }if(value == null) {
              return target;
          } else {
              if (withSpace && !target.endsWith(STRING_BLANK)) {
                  return target + STRING_BLANK + value;
              } else {
                  return target + value;
              }
          }
      }