@Override
            public void onClear() {
                reportClear();
            }
        };
    }

    private class TrackingEntry implements Map.Entry<Object, Object> {
        private final Map.Entry<Object, Object> delegate;

        TrackingEntry(Map.Entry<Object, Object> delegate) {
            this.delegate = delegate;
        }

        @Override
        public Object getKey() {