props.setProperty(FessEnv.MAIL_RETURN_PATH, "no-reply+bounce@example.co.jp");
                return props;
            }
        };

        assertEquals("smtp-relay.example.com:465", specialMailEnv.getMailSmtpServerMainHostAndPort());
        assertEquals("[テスト環境]", specialMailEnv.getMailSubjectTestPrefix());
        assertEquals("no-reply+bounce@example.co.jp", specialMailEnv.getMailReturnPath());
    }

        }

        @Override
        public String getMailFromName() {
            return "Fess System";
        }

        @Override
        public String getMailReturnPath() {
            return "bounce@example.com";
        }
    }

  }

  private static final int DISTINCT_CHARS = Character.MAX_VALUE - Character.MIN_VALUE + 1;

  /**
   * This is the actual implementation of {@link #precomputed}, but we bounce calls through a method
   * on {@link Platform} so that we can have different behavior in GWT.
   *
   * <p>This implementation tries to be smart in a number of ways. It recognizes cases where the