## Future { #future }

By this point, it's already clear that **FastAPI** with its ideas is being useful for many people.

It is being chosen over previous alternatives for suiting many use cases better.

  public void testClear() {
    table = create("foo", 1, 'a', "bar", 1, 'b', "foo", 3, 'c');
    if (supportsRemove()) {
      table.clear();
      assertEquals(0, table.size());
      assertFalse(table.containsRow("foo"));
    } else {
      assertThrows(UnsupportedOperationException.class, () -> table.clear());
    }
  }

  public void testPut() {
    assertThat(table.put("foo", 1, cellValue('a'))).isNull();

    table.put("b", "b", "x");
    table.put("b", "c", "y");
    table.put("b", "x", "n");
    table.put("a", "a", "d");
    table.row("b").subMap("c", "x").clear();
    assertEquals(table.row("b"), ImmutableMap.of("b", "x", "x", "n"));
    table.row("b").subMap("b", "y").clear();
    assertEquals(table.row("b"), ImmutableMap.of());
    assertFalse(table.backingMap.containsKey("b"));
  }

        originalMap.put("refreshKrb5Config", "true");

        @SuppressWarnings("unchecked")
        Map<String, Object> spyOpts = spy(originalMap);

        // Reset the spy to clear any prior invocations from setup
        reset(spyOpts);

        StaticJAASConfiguration cfg = new StaticJAASConfiguration(spyOpts);

        // Act

    @Override
    public @Nullable V remove(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return super.remove(object);
    }

    @Override
    public void clear() {
      assertTrue(Thread.holdsLock(mutex));
      super.clear();
    }

    @Override
    public boolean containsKey(Object key) {
      assertTrue(Thread.holdsLock(mutex));
      return super.containsKey(key);
    }

    @Override

      put(entry.getKey(), entry.getValue());
    }
  }

  @Override
  public void clear() {
    if (removalListener != null) {
      for (Entry<K, Timestamped<V>> entry : cachingHashMap.entrySet()) {
        alertListenerIfPresent(entry.getKey(), entry.getValue().getValue(), RemovalCause.EXPLICIT);
      }
    }
    cachingHashMap.clear();
  }

  @Override
  public V putIfAbsent(K key, V value) {

      this.fromCollection = checkNotNull(fromCollection);
      this.function = checkNotNull(function);
    }

    @Override
    public void clear() {
      fromCollection.clear();
    }

    @Override
    public boolean isEmpty() {
      return fromCollection.isEmpty();
    }

    @Override
    public Iterator<T> iterator() {

  }

  /**
   * A sensible definition of {@link #clear} in terms of the {@code iterator} method of {@link
   * #entrySet}. If you override {@link #entrySet}, you may wish to override {@link #clear} to
   * forward to this implementation.
   *
   * @since 7.0
   */
  @Override
  protected void standardClear() {
    Iterators.clear(entrySet().iterator());
  }

  /**

      assertTrue(Thread.holdsLock(mutex));
      return delegate.retainAll(collection);
    }

    @Override
    public void clear() {
      assertTrue(Thread.holdsLock(mutex));
      delegate.clear();
    }

    @Override
    public Object[] toArray() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toArray();
    }

    @Override

    checkNotNull(action);
    backingMap.forEach((element, count) -> action.accept(element, count.get()));
  }

  @Override
  public void clear() {
    for (Count frequency : backingMap.values()) {
      frequency.set(0);
    }
    backingMap.clear();
    size = 0L;
  }

  @Override
  int distinctElements() {
    return backingMap.size();
  }

  // Optimizations - Query Operations