如何在java中读取和写入整数到txt文件中以获得高分？

Question

嘿伙计们，在过去的几个小时里，我一直在努力弄清楚如何读取和写入高分数到txt文件。我不断收到代码中的错误，当我修复它们时会出现更多问题。我一直在尝试使用BufferedReaders和BufferedWriters，但有些尝试从未解决过。

顺便说一句，如果高分数等级（＆＃34;＆＃34;）我调用GetHighScore类，并且当玩家死亡时我调用CheckHighScore。

以下是我现在无法使用的代码：

public static int score = 0;

public static String highScore = "0";

public static String GetHighScore() {

    // I call this in my player class when highScore.equals("");

    BufferedReader reader = null;

    try {
        reader = new BufferedReader(new FileReader("res/Files/highscore.txt"));
        return reader.readLine();
    } catch (Exception e) {

        return "Make One";

    } finally {
        try {
            if (reader != null)
                reader.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

public static void CheckHighScore() {

    // I call this when i die to check the score

    if (score > Integer.parseInt(highScore)) {
        BufferedWriter writer = null;
        try {
            writer = new BufferedWriter(new FileWriter(
                    "res/Files/highscore.txt"));
            writer.write(score);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                writer.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

这是出现的错误：

Thread [Thread-3] (Suspended (exception NullPointerException))  
Player.tick() line: 123 
Game.tick() line: 127   
Game.run() line: 79 
Thread.run() line: not available