将Object数组转换为String数组

代码如下

//设备总数
List<String> strList = devices.stream().map(Device::getDevice_id).collect(Collectors.toList());
//将Object数组转换为String数组
String[] strByte = strList.toArray(new String[0]);
//将数组拼接成一个长的字符串
String devIds = String.join(",",strByte);