* </ul>
 *
 * <p>Usage:
 * <pre>
 * DynamicProperties dynamicProperties = new DynamicProperties("path/to/properties/file");
 * String value = dynamicProperties.getProperty("key");
 * dynamicProperties.setProperty("key", "newValue");
 * dynamicProperties.store();
 * </pre>
 *
 * <p>Exceptions:
 * <ul>
 *   <li>{@link FileAccessException} - Thrown if there are issues accessing the file.</li>

    private @Nullable T value;

    @Nullable T get() {
      return value;
    }

    void checkAndSet(@Nullable T expected, @Nullable T newValue) {
      if (value != expected) {
        throw new ConcurrentModificationException();
      }
      value = newValue;
    }

    void clear() {
      value = null;
    }
  }

  private static final class AvlNode<E extends @Nullable Object> {

      synchronized (mutex) {
        return delegate().putIfAbsent(key, value);
      }
    }

    @Override
    public boolean replace(K key, V oldValue, V newValue) {
      synchronized (mutex) {
        return delegate().replace(key, oldValue, newValue);
      }
    }

    @Override
    public @Nullable V replace(K key, V value) {
      synchronized (mutex) {

              }

              @Override
              @ParametricNullness
              public V setValue(@ParametricNullness V newValue) {
                checkArgument(apply(getKey(), newValue));
                return super.setValue(newValue);
              }
            };
          }
        };
      }
    }

    @Override
    Set<K> createKeySet() {

              }

              @Override
              @ParametricNullness
              public V setValue(@ParametricNullness V newValue) {
                checkArgument(apply(getKey(), newValue));
                return super.setValue(newValue);
              }
            };
          }
        };
      }
    }

    @Override
    Set<K> createKeySet() {