swap(array, from, to);
        }
        if (array[from + 1] > array[to]) {
          swap(array, from + 1, to);
        }
        if (array[from] > array[from + 1]) {
          swap(array, from, from + 1);
        }

        // Perform a partition with the selected median.
        int low = from + 1, high = to; // Indexes for partitioning.
        double partition = array[from + 1]; // Choose partitioning element.

          swap(array, from, to);
        }
        if (array[from + 1] > array[to]) {
          swap(array, from + 1, to);
        }
        if (array[from] > array[from + 1]) {
          swap(array, from, from + 1);
        }

        // Perform a partition with the selected median.
        int low = from + 1, high = to; // Indexes for partitioning.
        double partition = array[from + 1]; // Choose partitioning element.

    for (int i = to; i > from; i--) {
      if (array[i] > pivot) {
        swap(array, partitionPoint, i);
        partitionPoint--;
      }
    }

    // We now know that all elements with indexes in (from, partitionPoint] are less than or equal
    // to the pivot at from, and all elements with indexes in (partitionPoint, to] are greater than
    // it. We swap the pivot into partitionPoint and we know the array is partitioned around that.

    },
    ALMOST_SORTED {
      @Override
      void arrange(List<Integer> list) {
        Collections.sort(list);
        if (list.size() > 1) {
          int i = (list.size() - 1) / 2;
          Collections.swap(list, i, i + 1);
        }
      }
    },
    RANDOM {
      @Override
      void arrange(List<Integer> list) {}
    };

    abstract void arrange(List<Integer> list);
  }

 * desirable to use in some unit tests. More importantly, attempting to debug a call which is
 * time-limited would be extremely annoying, so this gives you a time-limiter you can easily swap in
 * for your real time-limiter while you're debugging.
 *
 * @author Kevin Bourrillion
 * @author Jens Nyman
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault

    },
    ALMOST_SORTED {
      @Override
      void arrange(List<Integer> list) {
        Collections.sort(list);
        if (list.size() > 1) {
          int i = (list.size() - 1) / 2;
          Collections.swap(list, i, i + 1);
        }
      }
    },
    RANDOM {
      @Override
      void arrange(List<Integer> list) {}
    };

    abstract void arrange(List<Integer> list);
  }

    //     [abc]de|[fgh] -> [fgh]de|[abc]. Now [fgh] is in the right place, but we need to swap [de]
    //     with [abc]: fgh[de]|a[bc] -> fgh[bc]|a[de]. Now we need to swap [a] with [bc]:
    //     fgh[b]c|[a]de -> fgh[a]c|[b]de. Finally we need to swap [c] with [b]:
    //     fgha[c]|[b]de -> fgha[b]|[c]de. Because these two blocks are the same size, we are done.

      RunnableExecutorPair(Runnable runnable, Executor executor) {
        this.runnable = runnable;
        this.executor = executor;
      }
    }
  }

  // A version of the list that uses compare and swap to manage the stack without locks.
  private static final class ExecutionListCAS {
    static final Logger log = Logger.getLogger(ExecutionListCAS.class.getName());

    private static final sun.misc.Unsafe UNSAFE;

       * requireNonNull is safe because we don't clear nextPermutation until we're done calling this
       * method.
       */
      requireNonNull(nextPermutation);

      int l = findNextL(j);
      Collections.swap(nextPermutation, j, l);
      int n = nextPermutation.size();
      Collections.reverse(nextPermutation.subList(j + 1, n));
    }

    int findNextJ() {
      /*

      if (comparator.compare(uncheckedCastNullableTToT(buffer[i]), pivotValue) < 0) {
        swap(pivotNewIndex, i);
        pivotNewIndex++;
      }
    }
    buffer[right] = buffer[pivotNewIndex];
    buffer[pivotNewIndex] = pivotValue;
    return pivotNewIndex;
  }

  private void swap(int i, int j) {
    T tmp = buffer[i];
    buffer[i] = buffer[j];
    buffer[j] = tmp;
  }