A accum = collector.supplier().get();
        for (T input : inputs) {
          collector.accumulator().accept(accum, input);
        }
        return accum;
      }
    },
    /** Get one accumulator for each element and merge the accumulators left-to-right. */
    MERGE_LEFT_ASSOCIATIVE {
      @Override
      final <T extends @Nullable Object, A extends @Nullable Object, R extends @Nullable Object>

        A accum = collector.supplier().get();
        for (T input : inputs) {
          collector.accumulator().accept(accum, input);
        }
        return accum;
      }
    },
    /** Get one accumulator for each element and merge the accumulators left-to-right. */
    MERGE_LEFT_ASSOCIATIVE {
      @Override
      final <T extends @Nullable Object, A extends @Nullable Object, R extends @Nullable Object>

  /**
   * Atomically updates the current value with the results of applying the given function to the
   * current and given values.
   *
   * @param x the update value
   * @param accumulatorFunction the accumulator function
   * @return the previous value
   * @since 31.1
   */
  @CanIgnoreReturnValue
  public final double getAndAccumulate(double x, DoubleBinaryOperator accumulatorFunction) {

          sb.append(iterator.next());
        }
      }
      dummy ^= sb.toString().length();
    }
    return dummy;
  }

  /**
   * Only appends delimiter if the accumulated string is non-empty. Note: this isn't a candidate
   * implementation for Joiner since it fails on leading empty components.
   */
  @Benchmark
  int stringBuilderIsEmpty(int reps) {
    int dummy = 0;