private String addOriginalLineNumbers() {
    StringBuilder sb = new StringBuilder();
    int lineStart = 0, lineEnd;
    int count = 0, length = myLineSeparator.length();
    while ((lineEnd = myStringBuilder.indexOf(myLineSeparator, lineStart)) > 0) {
      ++count;
      sb.append(myStringBuilder, lineStart, lineEnd);
      Set<Integer> integers = myLineMapping.get(count);
      if (integers != null) {
        sb.append("//");
        for (Integer integer : integers) {
          sb.append(' ').append(integer);
        }
      }
      sb.append(myLineSeparator);
      lineStart = lineEnd + length;
    }
    if (lineStart < myStringBuilder.length()) {
      sb.append(myStringBuilder.substring(lineStart));
    }
    return sb.toString();
  }
private String addOriginalLineNumbers()