java数据结构排序输出问题

Question

请问这些数据 在txt文档中读取
然后分别按照升序和降序排列输出到新的txt文档中，ps：(新的文档中
要有两次排序的结果)
求大神给出完整java代码，小弟弄了好久了都，

s1109853011,JackieChan,CS001,85
s0907451244,FranklinPapadias,MA002,65
s0308893477,MirandaLambert,HM467,35
s4045128481,SophiaPam,CM604,75
s0812340023,PhilipsChiu,CS001,71

Answer 1

不知道这个是不是你要的

 public class SortData {
    public static void main(String[] args) {
        String oldPath = "C:/Users/东海/Desktop/foo.txt";
        String newPath = "C:/Users/东海/Desktop/bar.txt";
        try {
            sortAndWriteData(oldPath, newPath);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private static void sortAndWriteData(String path, String newPath)
            throws IOException {
        ArrayList<HashMap<String, String>> list = getData(path);
        writeToText(list, newPath);
        Collections.sort(list, new Comparator<HashMap<String, String>>() {

            @Override
            public int compare(HashMap<String, String> o1,
                    HashMap<String, String> o2) {
                if (o1.get("id").compareTo(o2.get("id")) > 0) {
                    return 1;
                }
                if (o1.get("id").compareTo(o2.get("id")) < 0) {
                    return -1;
                }
                return 0;
            }

        });
        writeToText(list, newPath);

    }

    private static void writeToText(ArrayList<HashMap<String, String>> list,
            String newPath) throws IOException {
        File file = new File(newPath);
        BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file,true)));
        StringBuilder stringBuilder = new StringBuilder();
        for (HashMap<String, String> hashMap : list) {
            String data=stringBuilder.append(hashMap.get("id")+",")
                    .append(hashMap.get("name")+",").append(hashMap.get("unknown")+",")
                    .append(hashMap.get("num")).toString();
            bufferedWriter.write(data+"\r\n");
            bufferedWriter.flush();
            stringBuilder.delete(0, stringBuilder.length());
        }
        bufferedWriter.close();
    }

    private static ArrayList<HashMap<String, String>> getData(String path)
            throws IOException {
        ArrayList<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
        File file = new File(path);
        BufferedReader bufferedReader = new BufferedReader(new FileReader(file));
        String content = "";
        while (content != null) {
            content = bufferedReader.readLine();
            if (content == null) {
                break;
            }
            String[] dataArray = content.split(",");
            HashMap<String, String> map = new HashMap<String, String>();
            map.put("id", dataArray[0]);
            map.put("name", dataArray[1]);
            map.put("unknown", dataArray[2]);
            map.put("num", dataArray[3]);
            list.add(map);
            content = "";
        }
        bufferedReader.close();
        return list;
    }
}