关于Object[] 数组不能强转成String[]数组

笔记

Object[] ob = {"hello","World"};
String[] str = (String[]) ob;
Object[] objArr = list.toArray();//这样是对象数组
String keys[] = (String[])list.toArray();

//两种转换String[] 数组 报异常Exception in thread “main” java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.String]
原因是Object[] 数组不能强转成String[]数组;

网上如下解决办法

ArrayList list=new ArrayList();
list.add("..");
...
String[] str=new String[llist.size()];
list.toArray(str);