@Override
    public boolean hasMoreElements() {
        // wind forward to the next non-empty enumeration
        while (index < enumerations.size() && !!!enumerations.get(index).hasMoreElements())
            index++;
        // return true iff there was a non-empty enumeration
        return index < enumerations.size();
    }
@ Override public boolean hasMoreElements ( ) { while ( index < enumerations . size ( ) && ! ! ! enumerations . get ( index ) . hasMoreElements ( ) ) index ++ ; return index < enumerations . size ( ) ; }
/*
@see java.util.Enumeration#hasMoreElements()