java - 如何在 Java 中使用 math.random 从文本文件打印特定文本行？

Question

Hi, I'm a newbie to java. I need to code a program where a genie tells someone their fortune. For this program, I take in input from a program based on a random number (from math.random) and return the line of text from whichever number (1-100) they returned. Can someone help me approach this problem (preferably without the use of professional classes I do not understand). Thank you!

public void askFortune() 
{   
    Scanner input = new Scanner("fortunes.txt");
    double number = Math.random();
    int num = (int) number * 100;
    num += 1;
}

Answer 1

您可以尝试迭代扫描器，直到到达随机行或到达扫描器的末尾:

public void askFortune() {   
    Scanner input = new Scanner("fortunes.txt");
    double number = Math.random();
    int num = (int) number * 100;
    num += 1;
    int counter = 0;
    String line = "";

    while (counter < number) {
        if (!input.hasNextLine()) {
            break;
        }
        line = input.nextLine();
        ++counter;
    }

    if (counter == number) {
         System.out.println("Found line:\n" + line);
    }
    else {
        System.out.println("Input file does not have enough lines"); 
    }
}