public void test_exceptionChaining() {
        // Test exception chaining with multiple levels
        Exception rootCause = new Exception("Network timeout");
        Exception middleCause = new Exception("SSO provider unreachable", rootCause);
        SsoProcessException topException = new SsoProcessException("SSO authentication failed", middleCause);

        assertEquals("SSO authentication failed", topException.getMessage());

    try {
      sourceResult = getDone(localInputFuture);
    } catch (CancellationException e) {
      // TODO(user): verify future behavior - unify logic with getFutureValue in AbstractFuture. This
      // code should be unreachable with correctly implemented Futures.
      // Cancel this future and return.
      // At this point, inputFuture is cancelled and outputFuture doesn't exist, so the value of
      // mayInterruptIfRunning is irrelevant.

   *
   * <p>This method always throws an exception. The {@code RuntimeException} return type allows
   * client code to signal to the compiler that statements after the call are unreachable. Example
   * usage:
   *
   * <pre>
   * T doSomething() {
   *   try {
   *     return someMethodThatCouldThrowAnything();
   *   } catch (IKnowWhatToDoWithThisException e) {
   *     return handle(e);

        if (comparator.compare(ak, nextPermutation.get(l)) < 0) {
          return l;
        }
      }
      throw new AssertionError("this statement should be unreachable");
    }
  }

  /**
   * Returns a {@link Collection} of all the permutations of the specified {@link Collection}.
   *

   * they will be absent (unless they were already returned).
   *
   * If there are I/O problems during iteration, this iterator fails silently. For example, if the
   * hosting filesystem becomes unreachable, the iterator will omit elements rather than throwing
   * exceptions.
   *
   * **The caller must [close][Snapshot.close]** each snapshot returned by [Iterator.next]. Failing
   * to do so leaks open files!
   */

   *
   * <p>This method always throws an exception. The {@code RuntimeException} return type allows
   * client code to signal to the compiler that statements after the call are unreachable. Example
   * usage:
   *
   * <pre>
   * T doSomething() {
   *   try {
   *     return someMethodThatCouldThrowAnything();
   *   } catch (IKnowWhatToDoWithThisException e) {
   *     return handle(e);

   * appear in this multimap.
   */
  @Override
  public ImmutableSet<K> keySet() {
    return map.keySet();
  }

  @Override
  Set<K> createKeySet() {
    throw new AssertionError("unreachable");
  }

  /**
   * Returns an immutable map that associates each key with its corresponding values in the
   * multimap. Keys and values appear in the same order as in this multimap.
   */
  @Override

      }

    /**
     * Configure this client to retry or not when a connectivity problem is encountered. By default,
     * this client silently recovers from the following problems:
     *
     * * **Unreachable IP addresses.** If the URL's host has multiple IP addresses,
     *   failure to reach any individual IP address doesn't fail the overall request. This can
     *   increase availability of multi-homed services.
     *

   * appear in this multimap.
   */
  @Override
  public ImmutableSet<K> keySet() {
    return map.keySet();
  }

  @Override
  Set<K> createKeySet() {
    throw new AssertionError("unreachable");
  }

  /**
   * Returns an immutable map that associates each key with its corresponding values in the
   * multimap. Keys and values appear in the same order as in this multimap.
   */
  @Override

        if (comparator.compare(ak, nextPermutation.get(l)) < 0) {
          return l;
        }
      }
      throw new AssertionError("this statement should be unreachable");
    }
  }

  /**
   * Returns a {@link Collection} of all the permutations of the specified {@link Collection}.
   *