code: public ComparatorCondition eq(Number... values) {
          return new ComparatorCondition("=", this, new LiteralOperand(
                  new LinkedHashSet<Number>(Arrays.asList(values))));
      }
docs: Returns a <a href=
  "http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.SpecifyingConditions.html#ConditionExpressionReference.Comparators"
  >comparator condition</a> (that evaluates to true if the value of the
  current attribute is equal to the set of specified values) for building condition
  expression.