// have completed and we have processed them all.
  @CheckForNull private volatile Set<Throwable> seenExceptions = null;

  private volatile int remaining;

  private static final AtomicHelper ATOMIC_HELPER;

  private static final LazyLogger log = new LazyLogger(AggregateFutureState.class);

  static {
    AtomicHelper helper;

   * number of characters copied.
   */
  private int drain(byte[] b, int off, int len) {
    int remaining = Math.min(len, byteBuffer.remaining());
    byteBuffer.get(b, off, remaining);
    return remaining;
  }

      assertTrue(bb.remaining() >= chunkSize);
      for (int i = 0; i < chunkSize; i++) {
        out.write(bb.get());
      }
    }

    @Override
    protected void processRemaining(ByteBuffer bb) {
      assertFalse(remainingCalled);
      remainingCalled = true;
      assertEquals(ByteOrder.LITTLE_ENDIAN, bb.order());
      assertTrue(bb.remaining() > 0);

      assertTrue(bb.remaining() >= chunkSize);
      for (int i = 0; i < chunkSize; i++) {
        out.write(bb.get());
      }
    }

    @Override
    protected void processRemaining(ByteBuffer bb) {
      assertFalse(remainingCalled);
      remainingCalled = true;
      assertEquals(ByteOrder.LITTLE_ENDIAN, bb.order());
      assertTrue(bb.remaining() > 0);

  // & this future completes. Released when the future releases the reference to the running state
  private @Nullable Set<Throwable> seenExceptions = null;
  private int remaining;

  AggregateFutureState(int remainingFutures) {
    this.remaining = remainingFutures;
  }

  final Set<Throwable> getOrInitSeenExceptions() {
    if (seenExceptions == null) {
      seenExceptions = newHashSet();

      for (int i = 0; i < numNodesToRemove; ++i) {
        assertThat(graph.removeNode(nodeList.get(i))).isTrue();
      }

      assertThat(graph.nodes()).hasSize(NUM_NODES - numNodesToRemove);
      // Number of edges remaining is unknown (node's incident edges have been removed).
      AbstractGraphTest.validateGraph(graph);

      for (int i = numNodesToRemove; i < NUM_NODES; ++i) {
        assertThat(graph.removeNode(nodeList.get(i))).isTrue();

    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(0, empty.remaining());
  }

  public void testNullWriter() throws Exception {
    // create a null writer

    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(0, empty.remaining());
  }

  public void testNullWriter() throws Exception {
    // create a null writer

      E e1, E e2, E e3, E e4, E e5, E e6, E... remaining) {
    Comparable<?>[] contents = new Comparable<?>[6 + remaining.length];
    contents[0] = e1;
    contents[1] = e2;
    contents[2] = e3;
    contents[3] = e4;
    contents[4] = e5;
    contents[5] = e6;
    System.arraycopy(remaining, 0, contents, 6, remaining.length);
    return construct(Ordering.natural(), contents.length, (E[]) contents);

          int bufIndex = 0;
          int remaining = buffer.length;
          try (InputStreamReader reader = new InputStreamReader(byteSource.openStream(), cs)) {
            int nRead = 0;
            while (remaining > 0 && (nRead = reader.read(buffer, bufIndex, remaining)) != -1) {
              bufIndex += nRead;
              remaining -= nRead;
            }
            if (nRead == -1) {