code: @Override
      public Predicate and(Expression<Boolean> arg0, Expression<Boolean> arg1)
      {
          if (arg0 != null && arg1 != null)
          {
             return new ConjuctionPredicate((Predicate)arg0, (Predicate)arg1);
          }
          return null;
      }
docs: /*
  (non-Javadoc)
  
  @see
  javax.persistence.criteria.CriteriaBuilder#and(javax.persistence.criteria
  .Expression, javax.persistence.criteria.Expression)