这个程序是哪里不对？
//对元素为String的list进行排序。import java.io.BufferedReader;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.io.PrintWriter;import java.util.*;class ComparatorString implements Comparator<Object>{ public int compare(Object arg0, Object arg1) { String s0=(String)arg0; String s1=(String)arg1; int flag = s0.compareTo(s1); return flag; } }public class Test{ public static void main(String[] args) {List<String> list = new ArrayList<String>();ComparatorString cs = new ComparatorString();try {BufferedReader is = new BufferedReader(new FileReader("god.txt"));String s;while((s=is.readLine())!= null){list.add(s);}Collections.sort(list,cs);is.close();PrintWriter w = new PrintWriter("sort.txt");for(String line : list) w.println(line); w.close();} catch (FileNotFoundException e) {System.out.println("没有找到god文件");} catch (IOException e) {System.out.println("发生了IO异常");}}}? ? ?敬请指教！