private static void removeTrailingSpaces(final Document document, final int startOffset) {
      int endOffset = startOffset;

      final CharSequence charsSequence = document.getCharsSequence();

      for (int i = startOffset; i < charsSequence.length(); i++) {
        final char c = charsSequence.charAt(i);
        endOffset = i;
        if (c == '\n') {
          break;
        }
        if (c != ' ' && c != '\t') {
          return;
        }
      }

      document.deleteString(startOffset, endOffset);
    }
private static void removeTrailingSpaces(final Document document, final int startOffset)