code: private void checkSizeOfMarkupBlocksStructure(final int markupLevel) {
          if (markupLevel >= this.markupBlocks.length) {
              final int newLen = Math.max(markupLevel + 1, this.markupBlocks.length + MARKUP_BLOCKS_LEN);
              final int[] newMarkupBlocks = new int[newLen];
              Arrays.fill(newMarkupBlocks, 0);
              System.arraycopy(this.markupBlocks, 0, newMarkupBlocks, 0, this.markupBlocks.length);
              this.markupBlocks = newMarkupBlocks;
          }
      }
docs: /*
  -------------------------------
  Markup block and level handling
  -------------------------------