code: public boolean containsAll(String s) {
          int cp;
          for (int i = 0; i < s.length(); i += UTF16.getCharCount(cp)) {
              cp = UTF16.charAt(s, i);
              if (!contains(cp))  {
                  if (strings.size() == 0) {
                      return false;
                  }
                  return containsAll(s, 0);
              }
          }
          return true;
      }
docs: Returns true if there is a partition of the string such that this set contains each of the partitioned strings.
  For example, for the Unicode set [a{bc}{cd}]<br>
  containsAll is true for each of: "a", "bc", ""cdbca"<br>
  containsAll is false for each of: "acb", "bcda", "bcx"<br>
  @param s string containing characters to be checked for containment
  @return true if the test condition is met