@GwtIncompatible // NavigableMap
public final class TreeRangeMap<K extends Comparable, V> implements RangeMap<K, V> {

  private final NavigableMap<Cut<K>, RangeMapEntry<K, V>> entriesByLowerBound;

  /** Returns a new, empty {@link TreeRangeMap}. */
  public static <K extends Comparable, V> TreeRangeMap<K, V> create() {
    return new TreeRangeMap<>();
  }

  /**

    TreeRangeMap<Integer, Integer> coalesced = TreeRangeMap.create();
    coalesced.put(Range.atLeast(1), 1);
    coalesced.putCoalescing(Range.atMost(1), 1);
    TreeRangeMap<Integer, Integer> differentValues = TreeRangeMap.create();
    differentValues.put(Range.closedOpen(1, 2), 2);
    differentValues.put(Range.closedOpen(3, 4), 2);
    TreeRangeMap<Double, Integer> differentTypes = TreeRangeMap.create();