code: public PatternN and(Observable<? extends Object> other) {
          if (other == null) {
              throw new NullPointerException();
          }
          return new PatternN(observables, other);
      }
docs: Creates a pattern that matches when all previous observable sequences have an available element.
  
  @param other
  Observable sequence to match with the previous sequences.
  @return Pattern object that matches when all observable sequences have an available element.