Java每日小知识

1、BeanUtils.copyproperties(O1,O2),是把O1赋值给O2，注意O1的格式空格之类的

2、LinkedHashSet给集合快速去重，具体用法：

{

ArrayList numbersList = new ArrayList<>(Arrays.asList(1, 1, 2, 3, 3, 3, 4, 5, 6, 6, 6, 7, 8));

System.out.println(numbersList);

LinkedHashSet hashSet = new LinkedHashSet<>(numbersList);

ArrayList listWithoutDuplicates = new ArrayList<>(hashSet);

System.out.println(listWithoutDuplicates);

}

输出结果如下：[1, 1, 2, 3, 3, 3, 4, 5, 6, 6, 6, 7, 8]

                        [1, 2, 3, 4, 5, 6, 7, 8]