@Test
    public void test_append_emptyString() {
        StringBuilder buf = new StringBuilder();
        Supplier<Object> supplier = () -> "";

        monitorTarget.append(buf, "emptyKey", supplier);
        assertEquals("\"emptyKey\":\"\"", buf.toString());
    }

    // Test append with very long string
    @Test
    public void test_append_veryLongString() {
        StringBuilder buf = new StringBuilder();

        // setObject should handle various inputs
        try {
            WebApiUtil.setObject("validKey", "validValue");
            WebApiUtil.setObject("", "emptyKey");
            WebApiUtil.setObject("nullValue", null);
            WebApiUtil.setObject(null, "nullKey");
            WebApiUtil.setObject(null, null);
        } catch (Exception e) {

        source2.put("content", "Second content");

        indexExportJob.exportDocument(source1, tempDir.toString(), Collections.emptySet(), new HtmlIndexExportFormatter());
        indexExportJob.exportDocument(source2, tempDir.toString(), Collections.emptySet(), new HtmlIndexExportFormatter());

        final Path file = tempDir.resolve("example.com/page.html");

  ImmutableSetMultimap(
      ImmutableMap<K, ImmutableSet<V>> map,
      int size,
      @Nullable Comparator<? super V> valueComparator) {
    super(map, size);
    this.emptySet = emptySet(valueComparator);
  }

  // views

  /**
   * Returns an immutable set of the values for the given key. If no mappings in the multimap have

  ImmutableSetMultimap(
      ImmutableMap<K, ImmutableSet<V>> map,
      int size,
      @Nullable Comparator<? super V> valueComparator) {
    super(map, size);
    this.emptySet = emptySet(valueComparator);
  }

  // views

  /**
   * Returns an immutable set of the values for the given key. If no mappings in the multimap have

  protected abstract <E extends Comparable<? super E>> Set<E> copyOf(
      Iterator<? extends E> elements);

  public void testCreation_noArgs() {
    Set<String> set = of();
    assertEquals(Collections.<String>emptySet(), set);
    assertThat(set).isSameInstanceAs(this.<String>of());
  }

  public void testCreation_oneElement() {
    Set<String> set = of("a");
    assertEquals(singleton("a"), set);
  }

    assertThrows(IllegalStateException.class, iterable::iterator);
  }

  public void testFrom_empty() {
    Iterable<String> iterable = MinimalIterable.from(Collections.<String>emptySet());
    Iterator<String> iterator = iterable.iterator();
    assertFalse(iterator.hasNext());
    assertThrows(NoSuchElementException.class, iterator::next);
    assertThrows(IllegalStateException.class, iterable::iterator);

    assertThrows(IllegalStateException.class, iterable::iterator);
  }

  public void testFrom_empty() {
    Iterable<String> iterable = MinimalIterable.from(Collections.<String>emptySet());
    Iterator<String> iterator = iterable.iterator();
    assertFalse(iterator.hasNext());
    assertThrows(NoSuchElementException.class, iterator::next);
    assertThrows(IllegalStateException.class, iterable::iterator);

  private static final long RANDOM_SEED = 177L;

  public void testCombineOrdered_empty() {
    assertThrows(
        IllegalArgumentException.class,
        () -> Hashing.combineOrdered(Collections.<HashCode>emptySet()));
  }

  public void testCombineOrdered_differentBitLengths() {
    assertThrows(
        IllegalArgumentException.class,
        () -> {
          HashCode unused =

    assertTrue(multimap.entries().isEmpty());
    assertTrue(multimap.equals(HashMultimap.create()));
    assertEquals(emptySet(), multimap.get("foo"));
    assertEquals(0, multimap.hashCode());
    assertTrue(multimap.isEmpty());
    assertEquals(HashMultiset.create(), multimap.keys());
    assertEquals(emptySet(), multimap.keySet());
    assertEquals(0, multimap.size());
    assertTrue(multimap.values().isEmpty());