code: public static boolean containsAll(Set<String> target, Set<String> members) {
  		target = new HashSet<String>(target);
  		target.retainAll(members);
  		return target.size() == members.size();
  	}
docs: Compare 2 sets and check that one contains all members of the other.
  
  @param target set of strings to check
  @param members the members to compare to
  @return true if all members are in the target