java集合过滤出符合条件的List元素集合（lambda表达式）

使用Java8中的lambda表达式过滤

        ModelMap model = new ModelMap();
        TSmClazz TSmClazz = tSmClazzService.get(id);
        List<Student> students = TSmClazz.getStudents();
        if(flag.equals("0")){
            List<Student> boys =students.stream().filter(s->s.getSex().equals("0")).collect(Collectors.toList());
            model.put("data", boys);
        }else if(flag.equals("1")){
            List<Student> girls =students.stream().filter(s->s.getSex().equals("1")).collect(Collectors.toList());
            model.put("data", girls);
        }else{
            model.put("data", students);
        }