public Integer computeNext() {
            if (haveBeenCalled) {
              throw new AssertionError("Should not have been called again");
            } else {
              haveBeenCalled = true;
              throw sneakyThrow(new SomeCheckedException());
            }
          }
        };

    // The first time, the sneakily-thrown exception comes out
    assertThrows(SomeCheckedException.class, iter::hasNext);

          public Integer computeNext() {
            if (haveBeenCalled) {
              throw new AssertionError("Should not have been called again");
            } else {
              haveBeenCalled = true;
              throw sneakyThrow(new SomeCheckedException());
            }
          }
        };

    // The first time, the sneakily-thrown exception comes out
    assertThrows(SomeCheckedException.class, iter::hasNext);

  public boolean addAll(Collection<? extends E> elementsToAdd) {
    throw up();
  }

  @Override
  public boolean removeAll(Collection<?> elementsToRemove) {
    throw up();
  }

  @Override
  public boolean retainAll(Collection<?> elementsToRetain) {
    throw up();
  }

  @Override
  public void clear() {
    throw up();
  }

  private static UnsupportedOperationException up() {

          throw exceptionSupplier.get();
        } else {
          throw new NoSuchElementException();
        }
      } else if (extras.isEmpty()) {
        return uncheckedCastNullableTToT(element);
      } else {
        throw multiples(false);
      }
    }
  }

  private MoreCollectors() {}

   * {@code view} returned by this method will be invalidated, and will throw {@code
   * IllegalStateException} if it is accessed in any way, with the following exceptions:
   *
   * <ul>
   *   <li>{@code view.equals(view)} evaluates to {@code true} (but any other {@code equals()}
   *       expression involving {@code view} will throw)
   *   <li>{@code hashCode()} does not throw

   * {@code view} returned by this method will be invalidated, and will throw {@code
   * IllegalStateException} if it is accessed in any way, with the following exceptions:
   *
   * <ul>
   *   <li>{@code view.equals(view)} evaluates to {@code true} (but any other {@code equals()}
   *       expression involving {@code view} will throw)
   *   <li>{@code hashCode()} does not throw

            throw new UnsupportedOperationException();
        }

        @Override
        public String getLocalName() {
            throw new UnsupportedOperationException();
        }

        @Override
        public String getLocalAddr() {
            throw new UnsupportedOperationException();
        }

        @Override
        public int getLocalPort() {

    throw new UnsupportedOperationException();
  }

  /**
   * Guaranteed to throw an exception and leave the {@code RangeSet} unmodified.
   *
   * @throws UnsupportedOperationException always
   * @deprecated Unsupported operation.
   */
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public void remove(Range<C> range) {

   */
  @Override
  protected void tearDown() throws Exception {
    Throwable t = threadFailure.getAndSet(null);
    if (t != null) {
      if (t instanceof Error) {
        throw (Error) t;
      } else if (t instanceof RuntimeException) {
        throw (RuntimeException) t;
      } else if (t instanceof Exception) {
        throw (Exception) t;
      } else {

   * @param len an int specifying the number of bytes to read.
   * @throws EOFException if this stream reaches the end before reading all the bytes.
   * @throws IOException if an I/O error occurs.
   */
  public static void readFully(InputStream in, byte[] b, int off, int len) throws IOException {
    int read = read(in, b, off, len);
    if (read != len) {
      throw new EOFException(