}

    public User load(final User user) {
        User u = user;
        for (final AuthenticationChain chain : chains) {
            u = chain.load(u);
        }
        return u;
    }

    public void addChain(final AuthenticationChain chain) {
        chains = ArrayUtils.addAll(chains, chain);
    }

    protected StreamOf<AuthenticationChain> chains() {
        return stream(chains);
    }

            @Override
            public QueryBuilder execute(QueryContext context, Query query, float boost, FilterChain chain) {
                calledFirst.set(true);
                assertFalse(called.get());
                QueryBuilder builder = chain.execute(context, query, boost);
                assertTrue(called.get());
                return builder;
            }
        });

      // held
      chain = segment.newEntry(key, cache.hash(key), chain);
      if (i == 0) {
        head = chain;
      }
    }
  }

  @SuppressWarnings("GuardedBy")
  @Benchmark
  int time(int reps) {
    int dummy = 0;
    for (int i = 0; i < reps; i++) {
      // TODO(b/145386688): This access should be guarded by 'this.segment', which is not currently

   * already been determined.
   */
  public abstract <T extends @Nullable Object> ComparisonChain compare(
      @ParametricNullness T left, @ParametricNullness T right, Comparator<T> comparator);

  /**
   * Compares two {@code int} values as specified by {@link Ints#compare}, <i>if</i> the result of
   * this comparison chain has not already been determined.
   */

    protected static final String OPTIONS = "OPTIONS";

    @Override
    public void doFilter(final ServletRequest request, final ServletResponse response, final FilterChain chain)
            throws IOException, ServletException {
        final HttpServletRequest httpRequest = (HttpServletRequest) request;
        final String origin = httpRequest.getHeader("Origin");

  }

  /**
   * Gets a {@code Throwable} cause chain as a list. The first entry in the list will be {@code
   * throwable} followed by its cause hierarchy. Note that this is a snapshot of the cause chain and
   * will not reflect any subsequent changes to the cause chain.
   *
   * <p>Here's an example of how it can be used to find specific types of exceptions in the cause
   * chain:
   *
   * <pre>

  }

  /**
   * Gets a {@code Throwable} cause chain as a list. The first entry in the list will be {@code
   * throwable} followed by its cause hierarchy. Note that this is a snapshot of the cause chain and
   * will not reflect any subsequent changes to the cause chain.
   *
   * <p>Here's an example of how it can be used to find specific types of exceptions in the cause
   * chain:
   *
   * <pre>

   */
  abstract void collectOneValue(int index, @ParametricNullness InputT returnValue);

  abstract void handleAllCompleted();

  /** Adds the chain to the seen set, and returns whether all the chain was new to us. */
  private static boolean addCausalChain(Set<Throwable> seen, Throwable param) {
    // Declare a "true" local variable so that the Checker Framework will infer nullness.

  public void testFutureGetThrowsRuntimeException() throws Exception {
    BadFuture badInput = new BadFuture(Futures.immediateFuture(20));
    ListenableFuture<String> chain = buildChainingFuture(badInput);
    ExecutionException e = assertThrows(ExecutionException.class, () -> chain.get());
    assertSame(RuntimeException.class, e.getCause().getClass());
  }

  /** Proxy to throw a {@link RuntimeException} out of the {@link #get()} method. */

    firstException = expected;
    // Second time should also fail, with a cached causal chain.
    expected = assertThrows(PotentialDeadlockException.class, () -> lockA.lock());
    checkMessage(expected, "LockB -> LockA", "LockA -> LockB");
    // The causal chain should be cached.
    assertSame(firstException.getCause(), expected.getCause());
    // lockA should work after lockB is released.