java - 排序功能不排序! java

Question

下面是我的 Java 测验程序中的代码块。我正在尝试将高分读取/写入文件并对高分表进行排序。

public static void main(String[] args) throws IOException {

        sort(highscoreTable);
        int score1 = 0;
        int score2 = 0;
        int totalscore = 0;
        int NumberofQuestions = 5;

        // RECORDS TO STORE QUESTION, ANSWER WOULD BE HERE //

private static void start(int NumberofQuestions, String[] Answers, String[][] questions, int score1, int score2, int totalscore) throws IOException {
        // DISPLAYED ON THE HOME SCREEN SO USER CAN CHOOSE WHAT THEY WANT TO DO
        System.out.println("[0] Leave\n");
        while(true) {
            System.out.println("[1] Play");
            System.out.println("[2] Highscore");
            System.out.print("Enter Choice: ");
            String useranswer = scanner.nextLine();
            System.out.println();
            if (useranswer.equals("1")) {
                mainLoop(NumberofQuestions, Answers, questions, score1, score2, totalscore);
            } else if (useranswer.equals("2")) {
                sort(highscoreTable);
            } else if (useranswer.equals("0")) {
                try {
                    save();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                break;
            }
        }
    }

我希望这个位首先显示在屏幕上，如果用户按2，我想编程从文件中读取并显示之前的高分

 public static void save() throws IOException {

        String aggFileName = "agg-"+String.valueOf("06.txt");
        FileWriter fstream = new FileWriter(aggFileName);
        BufferedWriter out = new BufferedWriter(fstream);

        for (Map.Entry<String, String> entry : highscoreTable.entrySet()) {
            System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue()); //this statement prints out my keys and values
            out.write(entry.getKey() + "--" + entry.getValue() + "\n");
            System.out.println("Done");
            out.flush();   // Flush the buffer and write all changes to the disk
        }

        out.close();    // Close the file
    }

保存方法工作完美，我没有任何问题。

public static void mainLoop(int NumberofQuestions, String[]Answers, String[][] questions, int score1, int score2, int totalscore) throws IOException {

// USER WOULD ANSWER QUESTIONS HERE
        addHighscore(name, totalscore);
    }

public static void addHighscore(String name, int totalscore) throws IOException {
        highscoreTable.put(String.valueOf(totalscore), name);
    }

此处的函数将用户名和总分添加到树形图中

public static void highscoreImport(HashMap highscoreTable) throws IOException {

        String filePath = "agg-06.txt";
        String line;
        BufferedReader reader = new BufferedReader(new FileReader(filePath));
        while ((line = reader.readLine()) != null)
        {
            String[] parts = line.split("--", 2);
            if (parts.length >= 2)
            {
                String key = parts[0];
                String value = parts[1];
                highscoreTable.put(key, value);
            } else {
            }
        }
        for (Object key : highscoreTable.keySet())
        {
            System.out.println(key + "--" + highscoreTable.get(key));
        }

        reader.close();

    }

这是我遇到问题的部分。我希望程序从文件中获取信息，现在将其与来自用户最近测验的数据合并，然后对分数进行排序(我想要一个高分表)，以便当用户输入“2”时查看高分表，会按照降序排列

public static void sort(HashMap highscoreTable) throws IOException {

        System.out.println("Before Sorting:");
        Set set = highscoreTable.entrySet();
        Iterator iterator = set.iterator();
        while(iterator.hasNext()) {
            Map.Entry me = (Map.Entry)iterator.next();
            System.out.print(me.getKey() + ": ");
            System.out.println(me.getValue());
        }
        Map<Integer, String> map = new TreeMap<Integer, String>(highscoreTable);
        System.out.println("After Sorting:");
        Set set2 = map.entrySet();
        Iterator iterator2 = set2.iterator();
        while(iterator2.hasNext()) {
            Map.Entry me2 = (Map.Entry)iterator2.next();
            System.out.print(me2.getKey() + ": ");
            System.out.println(me2.getValue());
        }
    }

这里，排序“之前”和“之后”输出的列表是同一个未排序的列表

<小时/>

抱歉，阅读时间太长，如果您能提供帮助或指点来解决此问题，我将不胜感激。

Answer 1

自从在addHighscore你正在做的方法:

highscoreTable.put(String.valueOf(totalscore), name);

我认为它是 Map<String, String> (键和值类型均为 String )。

但是在 sort你这样做的方法...

Map<Integer, String> map = new TreeMap<Integer, String>(highscoreTable);

如果 highscoreTable 的类型被正确定义，TreeMap实例化应该在编译时失败。如果没有，则作为构造函数TreeMap(Map)按其键的自然顺序排序(请参阅 Javadoc)，它可能按 String 排序。订单或其他。因此“111”将位于“12”和其他意外结果之前。在所有集合和其他泛型类型类中定义类型是一个很好的做法。