問題描述有一個list集合，包含name，可空。date非空?，F在需要排序。需要name是null的排在前面，然后按照date排序問題出現的環(huán)境背景及自己嘗試過哪些方法list.sort();相關代碼//請把代碼文本粘貼到下方（請勿用圖片代替代碼）Listpeople=newArrayList();people.add(newPerson(1,null,sdf.parse("2019-09-2312:12:12")));people.add(newPerson(2,"1",sdf.parse("2019-09-2312:12:12")));people.add(newPerson(3,null,sdf.parse("2019-09-2412:12:12")));people.add(newPerson(4,"1",sdf.parse("2019-09-2412:12:12")));people.add(newPerson(5,null,sdf.parse("2019-09-1712:12:12")));people.add(newPerson(6,null,sdf.parse("2019-09-2412:12:12")));people.add(newPerson(8,null,sdf.parse("2019-09-2012:12:12")));people.add(newPerson(9,null,sdf.parse("2019-09-2312:12:12")));people.add(newPerson(10,"1",sdf.parse("2019-09-2012:12:12")));people.sort((t1,t2)->{if(t1.getName()==null&&t2.getName()!=null){return-1;}elseif(t2.getName()==null&&t1.getName()!=null){return-1;}elseif(Objects.equals(t1.getName(),t2.getName())){returnt1.getEntryDate().compareTo(t2.getEntryDate());}else{returnt1.getName().compareTo(t2.getName());}});System.out.println("SORT===========================");println(people);你期待的結果是什么？實際看到的錯誤信息又是什么？期望結果：Person[id=5,name=null,entryDate=2019-09-1712:12:12]Person[id=8,name=null,entryDate=2019-09-2012:12:12]Person[id=9,name=null,entryDate=2019-09-2312:12:12]Person[id=1,name=null,entryDate=2019-09-2312:12:12]Person[id=3,name=null,entryDate=2019-09-2412:12:12]Person[id=6,name=null,entryDate=2019-09-2412:12:12]Person[id=10,name=1,entryDate=2019-09-2012:12:12]Person[id=2,name=1,entryDate=2019-09-2312:12:12]Person[id=4,name=1,entryDate=2019-09-2412:12:12]輸出結果：SORT===========================Person[id=10,name=1,entryDate=2019-09-2012:12:12]Person[id=5,name=null,entryDate=2019-09-1712:12:12]Person[id=8,name=null,entryDate=2019-09-2012:12:12]Person[id=9,name=null,entryDate=2019-09-2312:12:12]Person[id=4,name=1,entryDate=2019-09-2412:12:12]Person[id=3,name=null,entryDate=2019-09-2412:12:12]Person[id=2,name=1,entryDate=2019-09-2312:12:12]Person[id=1,name=null,entryDate=2019-09-2312:12:12]Person[id=6,name=null,entryDate=2019-09-2412:12:12]