Collections.sort

例子1

Collections.sort(gradeResponses, Comparator.comparingInt(g -> NumberUtils.toInt(g.getCode(), 10000)));

例子2

Collections.sort(gradeResponses, (g1,g2)-> g1.getCode().compareTo(g2.getCode()));

例子3

Collections.sort(gradeResponses, Comparator.comparing(GradeResponse::getCode));

forEach

gradeResponses.forEach(s -> System.out.println(s));