SortCriteria defines a SortOrder, which contains an attribute name and an order type (ASCENDING or DESCENDING).
Query query = new Query();
query.select("c.lname, c.fname");
query.from("Customer", "c");
AttributeTest aTest = new AttributeTest();
aTest.setAttribute("state");
aTest.setTestValue("CA");
aTest.setTestType(AttributeTest.EQUAL);
query.setTestCriteria(aTest);
SortCriteria sort = new SortCriteria();
sort.add("lname", SortOrderType.ASCENDING);
sort.add("fname", SortOrderType.ASCENDING);
query.setSortCriteria(sort);