Map<String, List<String>> headers = new HashMap<>();
        headers.put(null, Arrays.asList("value"));
        headers.put("Content-Type", Arrays.asList("application/json"));

        response.setHeaders(headers);

        Map<String, List<String>> result = response.getHeaders();
        assertNotNull(result);
        assertEquals(1, result.size()); // null key should be filtered out
        assertTrue(result.containsKey("content-type"));

    toPut.put(null, 1);
    ImmutableListMultimap.Builder<String, Integer> builder = ImmutableListMultimap.builder();
    assertThrows(NullPointerException.class, () -> builder.put(null, 1));
    assertThrows(NullPointerException.class, () -> builder.putAll(null, Arrays.asList(1, 2, 3)));
    assertThrows(NullPointerException.class, () -> builder.putAll(null, 1, 2, 3));
    assertThrows(

   * Returns an arbitrary instance for {@code type}, or {@code null} if no arbitrary instance can be
   * determined.
   */
  public static <T> @Nullable T get(Class<T> type) {
    T defaultValue = DEFAULTS.getInstance(type);
    if (defaultValue != null) {
      return defaultValue;
    }
    Class<? extends T> implementation = getImplementation(type);
    if (implementation != null) {
      return get(implementation);
    }

     * StringUtil.defaultString("aaa", "NULL") = "aaa"
     * StringUtil.defaultString("aaa", null)   = "aaa"
     * StringUtil.defaultString(null, null)    = null
     * </pre>
     *
     * @param str
     *            the string (can be <code>null</code>)
     * @param defaultStr
     *            the string to return if the argument is <code>null</code> (can be <code>null</code>)

        assertThat(StringUtil.defaultString("aaa", "NULL"), is("aaa"));
        assertThat(StringUtil.defaultString("aaa", null), is("aaa"));
        assertThat(StringUtil.defaultString(null, null), is(nullValue()));
    }

    @Test
    public void testNewStringUnsafe() {
        assertNull(StringUtil.newStringUnsafe(null));
        char[] chars = new char[0];
        assertThat(StringUtil.newStringUnsafe(chars), is(""));

                    continue;
                }

                final String[] values = KuromojiCSVUtil.parse(replacedLine);
                String token = null;
                String segmentation = null;
                String reading = null;
                String pos = null;
                switch (values.length) {
                case 4:
                    pos = values[3];
                case 3:

  private Set<DurationSpec> expireAfterAccesses = Sets.newHashSet((DurationSpec) null);
  private Set<DurationSpec> refreshes = Sets.newHashSet((DurationSpec) null);
  private Set<Strength> keyStrengths = Sets.newHashSet((Strength) null);
  private Set<Strength> valueStrengths = Sets.newHashSet((Strength) null);

  @CanIgnoreReturnValue
  CacheBuilderFactory withConcurrencyLevels(Set<Integer> concurrencyLevels) {

- Fixes creationTimestamp: null causing unnecessary writes to etcd ([#116865](https://github.com/kubernetes/kubernetes/pull/116865), [@alexzielenski](https://github.com/alexzielenski)) [SIG API Machinery and Testing]

    if (sslSocket is BCSSLSocket) {
      when (val protocol = (sslSocket as BCSSLSocket).applicationProtocol) {
        // Handles both un-configured and none selected.
        null, "" -> null

        else -> protocol
      }
    } else {
      super.getSelectedProtocol(sslSocket)
    }

  companion object {
    val isSupported: Boolean =
      try {

  }

  public void testNull() {
    assertThrows(NullPointerException.class, () -> map.put(null, new Integer(1)));
    map.putInstance(Integer.class, null);
    assertThat(map.get(Integer.class)).isNull();
    assertThat(map.getInstance(Integer.class)).isNull();

    map.put(Long.class, null);
    assertThat(map.get(Long.class)).isNull();
    assertThat(map.getInstance(Long.class)).isNull();
  }