Java List去掉重複對象-java8

 

List<Object>去重方法一： 

    private List<Account> removeDupById(List<Account> accs) {
        Set<Account> accSet = new TreeSet<>(Comparator.comparing(Account::getId));
        accSet.addAll(accs);
        return new ArrayList<>(accSet);
    }

List<Object>去重方法二： 

    ArrayList<Account> distinctById = list.stream().collect(Collectors.collectingAndThen(
                Collectors.toCollection(() -> new TreeSet<>(
                        Comparator.comparing(Account::getId))), ArrayList::new));

字符串類型去重

List<String> strings = list.stream().distinct().collect(Collectors.toList());