game.txt

count=0

GameNumber.java

package LearnJava15;

import java.util.Random;
import java.util.Scanner;

public class GuessNumber {
    private GuessNumber() {
    }

    public static void start() {
        Random r = new Random();
        int number = r.nextInt(100) + 1;

        while (true) {
            Scanner sc = new Scanner(System.in);
            System.out.println("请输入你要猜的数字:");
            int guessNumber = sc.nextInt();
            if (guessNumber > number) {
                System.out.println("猜大了！");
            } else if ((guessNumber < number)) {
                System.out.println("猜小了！");
            } else {
                System.out.println("猜中了！");
                break;
            }

        }
    }
}

PorepertiesTest.java

package LearnJava15;

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Properties;

public class PorepertiesTest {
    public static void main(String[] args) throws IOException {
//        从文件中读取数据到集合中
        Properties prop = new Properties();
        FileReader fr = new FileReader("D:\\MyProject\\Java\\Demo2\\src\\LearnJava15\\game.txt");
        prop.load(fr);
        fr.close();
//        通过集合获取到玩游戏的方法
        String count = prop.getProperty("count");
        int number = Integer.parseInt(count);

        if (number >= 3) {
            System.out.println("游戏已结束，想玩请充钱！");
        } else {
//            玩游戏
            GuessNumber.start();
//             次数+1，重新写入文件
            number++;
            prop.setProperty("count", String.valueOf(number));
            FileWriter fw = new FileWriter("D:\\MyProject\\Java\\Demo2\\src\\LearnJava15\\game.txt");
            prop.store(fw, null);
            fw.close();
        }
    }
}

效果

请输入你要猜的数字:
70
猜小了！
请输入你要猜的数字:
100
猜大了！
请输入你要猜的数字:
85
猜小了！
99
猜中了！