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List list = new ArrayList();
list.add("1");
list.add("2");
final int size = list.size();
String[] arr = (String[])list.toArray(new String[size]);
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String[] userid = {"aa","bb","cc"};
List<String> userList = new ArrayList<String>();
Collections.addAll(userList, userid);
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List stooges = Arrays.asList("Larry", "Moe", "Curly");
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String[] arr = new String[] {"1", "2"};
List list = Arrays.asList(arr);
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