/guava/android/guava/src/com/google/common/collect/TreeBasedTable.java
this.lowerBound = upperBound;
this.lowerBound = lowerBound;
@CheckForNull final C upperBound; TreeRow(R rowKey) { this(rowKey, null, null); } TreeRow(R rowKey, @CheckForNull C lowerBound, @CheckForNull C upperBound) { super(rowKey); <extra_id_0> this.upperBound = upperBound; checkArgument( lowerBound == null || upperBound == null || compare(lowerBound, upperBound) <= 0); } @Override public SortedSet<C> keySet() {