private int value;

    @Override
    public Integer get() {
      return ++value;
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      if (obj instanceof CountingSupplier) {
        return this.value == ((CountingSupplier) obj).value;
      }
      return false;
    }

    @Override

    }
    expectUnchanged();
  }

  @CollectionFeature.Require(
      value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES},
      absent = RESTRICTS_ELEMENTS)
  public void testAdd_nullSupported() {
    assertTrue("add(null) should return true", collection.add(null));
    expectAdded((E) null);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testAdd_nullUnsupported() {

    }
    expectUnchanged();
  }

  @CollectionFeature.Require(
      value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES},
      absent = RESTRICTS_ELEMENTS)
  public void testAdd_nullSupported() {
    assertTrue("add(null) should return true", collection.add(null));
    expectAdded((E) null);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testAdd_nullUnsupported() {

   */
  EXPLICIT {
    @Override
    boolean wasEvicted() {
      return false;
    }
  },

  /**
   * The entry itself was not actually removed, but its value was replaced by the user. This can
   * result from the user invoking {@link Cache#put}, {@link LoadingCache#refresh}, {@link Map#put},
   * {@link Map#putAll}, {@link ConcurrentMap#replace(Object, Object)}, or {@link

  }

  private static final class MockCallback implements FutureCallback<String> {
    @Nullable private String value = null;
    @Nullable private Throwable failure = null;
    private boolean wasCalled = false;
    private final Object monitor = new Object();

    MockCallback(String expectedValue) {
      this.value = expectedValue;
    }

    MockCallback(Throwable expectedFailure) {
      this.failure = expectedFailure;

    server.enqueue(
      MockResponse
        .Builder()
        .addHeader("SeNsItIvE", "Value")
        .addHeader("Not-Sensitive", "Value")
        .build(),
    )
    val response =
      client
        .newCall(
          request()
            .addHeader("SeNsItIvE", "Value")
            .addHeader("Not-Sensitive", "Value")
            .build(),
        ).execute()
    response.body.close()

    void testRangeValidation(long value, long min, long max, boolean valid) {
        if (valid) {
            assertDoesNotThrow(() -> InputValidator.validateRange(value, min, max, "test"));
        } else {
            assertThrows(IllegalArgumentException.class, () -> InputValidator.validateRange(value, min, max, "test"));
        }
    }

   * }
   *
   * <p>{@code function} will never be invoked with a null value.
   *
   * <p>Note that {@code function} must be consistent according to {@code this} equivalence
   * relation. That is, invoking {@link Function#apply} multiple times for a given value must return
   * equivalent results. For example, {@code

     * @param id the encoded ID to convert
     * @return PathInfo object with separated path and name
     */
    public static PathInfo convertToItem(final String id) {
        final String value = decodeId(id);
        final String[] values = split(value, "/").get(stream -> stream.filter(StringUtil::isNotEmpty).toArray(n -> new String[n]));
        if (values.length == 0) {
            // invalid?

When writing request headers, use `header(name, value)` to set the only occurrence of `name` to `value`. If there are existing values, they will be removed before the new value is added. Use `addHeader(name, value)` to add a header without removing the headers already present.