() -> COMMA_SPLITTER.withKeyValueSeparator(":").split("a:1,b:2,a:3"));
  }

  public void testMapSplitter_varyingTrimLevels() {
    MapSplitter splitter = COMMA_SPLITTER.trimResults().withKeyValueSeparator(Splitter.on("->"));
    Map<String, String> split = splitter.split(" x -> y, z-> a ");
    assertThat(split).containsEntry("x ", " y");
    assertThat(split).containsEntry("z", " a");
  }

        if (params == null) {
            params = split(getCrawlerMetadataNameMapping(), "\n").get(stream -> stream.filter(StringUtil::isNotBlank).map(v -> {
                final String[] values = v.split("=");
                if (values.length == 2) {
                    final String[] subValues = values[1].split(":", 3);
                    if (subValues.length == 3) {

      }
    }
    OptionalState state = new OptionalState();

    Deque<Spliterator<T>> splits = new ArrayDeque<>();
    splits.addLast(stream.spliterator());

    while (!splits.isEmpty()) {
      Spliterator<T> spliterator = splits.removeLast();

      if (spliterator.getExactSizeIfKnown() == 0) {
        continue; // drop this split
      }

        assertNotNull(arrayFields);
        assertEquals(2, arrayFields.length);

        String[] dateFields = fessConfig.getIndexAdminDateFields().split(",");
        assertNotNull(dateFields);
        assertEquals(3, dateFields.length);

        String[] requiredFields = fessConfig.getIndexAdminRequiredFields().split(",");
        assertNotNull(requiredFields);

    public void test_beginDone() {
        String key = "test";
        crawlerStatsHelper.begin(key);
        crawlerStatsHelper.done(key);
        logger.info(localLogMsg.get());
        String[] values = localLogMsg.get().split("\t");
        assertEquals(3, values.length);
        assertEquals("url:test", values[0]);
        assertTrue(values[1].startsWith("time:"));
        assertTrue(values[2].startsWith("done:"));

    }

    @Test
    @DisplayName("Test split returns null when no following message")
    void testSplitWithNoFollowingMessage() {
        // Given
        when(request.split()).thenReturn(null);

        // When
        CommonServerMessageBlockRequest result = request.split();

        // Then
        assertNull(result);
        verify(request, times(1)).split();
    }

     */
    public static StreamOf<String> split(final String value, final String regex) {
        return stream(value == null ? null : value.split(regex));
    }

    /**
     * Creates a stream of map entries from the given map.
     *
     * @param <K> the type of keys in the map
     * @param <V> the type of values in the map

        }
        fessConfig = ComponentUtil.getFessConfig();
        split(fessConfig.getSuggestFieldContents(), ",")
                .of(stream -> stream.filter(StringUtil::isNotBlank).forEach(contentFieldNameSet::add));
        split(fessConfig.getSuggestFieldTags(), ",").of(stream -> stream.filter(StringUtil::isNotBlank).forEach(tagFieldNameSet::add));

        int version = 8;
        if (javaVersion != null) {
            final String[] split = javaVersion.split("[\\._]");
            if (split.length > 0) {
                version = Integer.parseInt(split[0]);
                if (version == 1 && split.length > 1) {
                    version = Integer.parseInt(split[1]);
                }
            }
        }
        return version;
    }

// The iterator yields the same subslices that would be returned by [Split](s, sep),
// but without constructing a new slice containing the subslices.
// It returns a single-use iterator.
func SplitSeq(s, sep []byte) iter.Seq[[]byte] {
	return splitSeq(s, sep, 0)
}

// SplitAfterSeq returns an iterator over subslices of s split after each instance of sep.