List<String> names=new ArrayList<String>();
names.add("1");
names.add("2");
names.add("3");
System.out.println(String.join("-", names));
String[] arrStr=new String[]{"a","b","c"};
System.out.println(String.join("-", arrStr));
输出： 1-2-3 a-b-c
原文：https://blog.csdn.net/lyylkj12/article/details/46709883
