rangeMap.put(Range.closedOpen(18, 19), 3);

    rangeMap.putCoalescing(Range.closedOpen(-5, -4), 0); // disconnected
    rangeMap.putCoalescing(Range.closedOpen(-6, -5), 0); // lower than minimum

    rangeMap.putCoalescing(Range.closedOpen(2, 4), 1); // between
    rangeMap.putCoalescing(Range.closedOpen(9, 14), 0); // different value
    rangeMap.putCoalescing(Range.closedOpen(17, 20), 3); // enclosing

    if (!range.isEmpty()) {
      checkNotNull(value);
      remove(range);
      entriesByLowerBound.put(range.lowerBound, new RangeMapEntry<K, V>(range, value));
    }
  }

  @Override
  public void putCoalescing(Range<K> range, V value) {
    // don't short-circuit if the range is empty - it may be between two ranges we can coalesce.
    if (entriesByLowerBound.isEmpty()) {
      put(range, value);
      return;
    }

    if (!range.isEmpty()) {
      checkNotNull(value);
      remove(range);
      entriesByLowerBound.put(range.lowerBound, new RangeMapEntry<K, V>(range, value));
    }
  }

  @Override
  public void putCoalescing(Range<K> range, V value) {
    // don't short-circuit if the range is empty - it may be between two ranges we can coalesce.
    if (entriesByLowerBound.isEmpty()) {
      put(range, value);
      return;
    }

   *
   * @throws UnsupportedOperationException always
   * @deprecated Unsupported operation.
   */
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public final void putCoalescing(Range<K> range, V value) {
    throw new UnsupportedOperationException();
  }

  /**
   * Guaranteed to throw an exception and leave the {@code RangeMap} unmodified.
   *