Object expectedKey = alternatingKeysAndValues[2 * i];
      Object expectedValue = alternatingKeysAndValues[2 * i + 1];
      Entry<Object, Object> expectedEntry = immutableEntry(expectedKey, expectedValue);
      assertEquals(expectedEntry, entries.get(i));
      assertEquals(expectedKey, keys.get(i));
      assertEquals(expectedValue, values.get(i));
    }
  }

  public void testAllocArraysDefault() {

      Object expectedKey = alternatingKeysAndValues[2 * i];
      Object expectedValue = alternatingKeysAndValues[2 * i + 1];
      Entry<Object, Object> expectedEntry = immutableEntry(expectedKey, expectedValue);
      assertEquals(expectedEntry, entries.get(i));
      assertEquals(expectedKey, keys.get(i));
      assertEquals(expectedValue, values.get(i));
    }
  }

  public void testAllocArraysDefault() {

  }

  public void testCompletedFuture(@Nullable Object expectedValue)
      throws InterruptedException, ExecutionException {
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());

    assertTrue(latch.await(5, SECONDS));
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());

    assertEquals(expectedValue, future.get());
  }

    @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;
    }

    @Override
    public void onSuccess(String result) {

        for (Thread thread : threads) {
            thread.join();
        }

        // All results should be the same
        String expectedValue = "Test Fess";
        for (String result : results) {
            assertEquals(expectedValue, result);
        }
    }

    // Test with non-existent config
    public void test_initialize_invalidConfigFile() {

      int initialSize = map.size();
      // var oldValue = map.get(keyToRemove);
      map.remove(keyToRemove);
      // This line doesn't hold - see the Javadoc comments above.
      // assertEquals(expectedValue, oldValue);
      assertFalse(map.containsKey(keyToRemove));
      assertEquals(initialSize - 1, map.size());
    } else {
      assertThrows(UnsupportedOperationException.class, () -> map.remove(keyToRemove));
    }

                        .replace("_", ".")
                        .replaceAll("\\.placeholder$", ".placeholder")
                        .replaceAll("\\.placeholder\\.(.+)", ".placeholder_$1");

                String expectedValue = "{labels." + expectedValuePart + "}";

                // Some fields may have different conventions, so we just check if it starts correctly

      return;
    }
    K keyToRemove = map.keySet().iterator().next();
    if (supportsRemove) {
      int initialSize = map.size();
      V expectedValue = map.get(keyToRemove);
      V oldValue = map.remove(keyToRemove);
      assertEquals(expectedValue, oldValue);
      assertFalse(map.containsKey(keyToRemove));
      assertEquals(initialSize - 1, map.size());
    } else {

        int initialSize = map.size();
        // var oldValue = map.get(keyToRemove);
        map.remove(keyToRemove);
        // This line doesn't hold - see the Javadoc comments above.
        // assertEquals(expectedValue, oldValue);
        assertFalse(map.containsKey(keyToRemove));
        assertEquals(initialSize - 1, map.size());
      } else {
        assertThrows(UnsupportedOperationException.class, () -> map.remove(keyToRemove));