code: public Criteria in(Collection<?> c) {
          notNull(c, "collection can not be null");
          this.criteriaType = RelationalOperator.IN;
          this.right = new ValueListNode(c);
          return this;
      }
docs: The <code>in</code> operator is analogous to the SQL IN modifier, allowing you
  to specify an array of possible matches.
  
  @param c the collection containing the values to match against
  @return the criteria