Jdk1.8新知识

Posted by zjh on September 7, 2020

集合流的使用

Integer数组转String集合

Arrays.stream(ids).map(Object::toString).collect(Collectors.toList())
# 或者是
Arrays.stream(ids).map(integer -> integer.toString()).collect(Collectors.toList());

集合转指定类型数组

List<Integer> list = new ArrayList<>();
Integer[] integers = list.toArray(new Integer[0]);