code: public boolean contentEquals(CharSequence x) {
          if (x == this) return true;
          if (isEmpty()) return x.length() == 0;
          int sz = size(), sz2 = x.length();
          if (sz != sz2) return false;
          for (int i = 0; i < sz; ++i) {
              char c = buf[toInternalId(i)];
              char c1 = x.charAt(i);
              if (c != c1) return false;
          }
          return true;
      }
docs: Wrapper of {@link String#contentEquals(CharSequence)}
  
  @param x the char sequence to be compared
  @return true if content equals content of the specified char sequence