s.updateLock.Lock()
	defer s.updateLock.Unlock()

	seenBefore := s.sourcesSeen.Has(source)
	adds, updates, deletes, removes, reconciles := s.merge(source, change)
	firstSet := !seenBefore && s.sourcesSeen.Has(source)

	// deliver update notifications
	switch s.mode {
	case PodConfigNotificationIncremental:
		if len(removes.Pods) > 0 {
			s.updates <- *removes
		}

        List<T> result = new ArrayList<T>();
        Iterator<? extends Collection<T>> iterator = availableValuesByDescriptor.iterator();
        if (iterator.hasNext()) {
            Collection<T> firstSet = iterator.next();
            result.addAll(firstSet);
            while (iterator.hasNext()) {
                Collection<T> next = iterator.next();
                result.retainAll(next);
            }
        }
        return result;

        List<T> result = new ArrayList<T>();
        Iterator<? extends Collection<T>> iterator = availableValuesByDescriptor.iterator();
        if (iterator.hasNext()) {
            Collection<T> firstSet = iterator.next();
            result.addAll(firstSet);
            while (iterator.hasNext()) {
                Collection<T> next = iterator.next();
                result.retainAll(next);
            }
        }
        return result;

                    events "passed", "skipped", "failed"
                }
            }
        """.stripIndent()

        and:
        file("src/test/java/FirstTest.java") << """
            ${testFrameworkImports}
            public class FirstTest {
                @Test public void test() {}
            }
        """.stripIndent()

        file("src/test/java/SecondTest.java") << """

      return new TreeRow(rowKey, fromKey, upperBound);
    }

    @Override
    public C firstKey() {
      updateBackingRowMapField();
      if (backingRowMap == null) {
        throw new NoSuchElementException();
      }
      return ((SortedMap<C, V>) backingRowMap).firstKey();
    }

    @Override
    public C lastKey() {
      updateBackingRowMapField();

      return new TreeRow(rowKey, fromKey, upperBound);
    }

    @Override
    public C firstKey() {
      updateBackingRowMapField();
      if (backingRowMap == null) {
        throw new NoSuchElementException();
      }
      return ((SortedMap<C, V>) backingRowMap).firstKey();
    }

    @Override
    public C lastKey() {
      updateBackingRowMapField();

			ext := tok.String()
			curArrangement, err := arch.ARM64RegisterArrangement(reg, name, ext)
			if err != nil {
				p.errorf(err.Error())
			}
			if firstReg == -1 {
				// only record the first register and arrangement
				firstReg = int(reg)
				nextReg = firstReg
				arrangement = curArrangement
			} else if curArrangement != arrangement {
				p.errorf("inconsistent arrangement in ARM64 register list")

	// more than one of each per m, p, and goroutine.
	firstGen := traceNextGen(trace.lastNonZeroGen)

	// Reset GC sequencer.
	trace.seqGC = 1

	// Reset trace reader state.
	trace.headerWritten = false
	trace.readerGen.Store(firstGen)
	trace.flushedGen.Store(0)

	// Register some basic strings in the string tables.
	traceRegisterLabelsAndReasons(firstGen)

	// Stop the world.
	//

    return ImmutableSortedSet.copyOf(comparator, sortedDelegate.keySet());
  }

  public Comparator<? super K> comparator() {
    return comparator;
  }

  @CheckForNull
  public K firstKey() {
    return sortedDelegate.firstKey();
  }

  @CheckForNull
  public K lastKey() {
    return sortedDelegate.lastKey();
  }

  @CheckForNull
  K higher(K k) {

  }

  public void testRowMapFirstKey() {
    sortedTable = create("foo", 1, 'a', "bar", 1, 'b', "foo", 3, 'c');
    assertSame("bar", sortedTable.rowMap().firstKey());
  }

  public void testRowMapLastKey() {
    sortedTable = create("foo", 1, 'a', "bar", 1, 'b', "foo", 3, 'c');
    assertSame("foo", sortedTable.rowMap().lastKey());
  }