檢索ArrayList中的隨機元素

Question

public class guessMovies {
private Random randomGenerator;
public static void main(String[] args) throws IOException {

    String MovieList = null;

    try (BufferedReader br = new BufferedReader(new FileReader("Movielist.txt"))) {

        while ((MovieList = br.readLine()) != null) {
            ArrayList<String> MovieNames = new ArrayList<String>();
            MovieNames.addAll(Arrays.asList(MovieList));
            //System.out.println(MovieList);
            System.out.println(MovieNames);

            Random r = new Random();
            System.out.print(MovieNames.get(r.nextInt(MovieNames.size)));
        }
    }

    catch(FileNotFoundException exception) {
        System.out.println("I cannot find your file");
    }
    //pick random movie
}

有人可以指導我如何在 Movielist 文件中隨機選擇電影標題，我可以打印出整個列表，但我不確定如何隨機選擇其中一個。

Answer 1

您應該實例化一個 ArrayList，讀取所有電影標題並將它們添加到列表中，然后使用 Random.nextInt() 選擇一個並打印它。

Answer 2

嘗試這樣的事情：

public class guessMovies {

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

        String MovieList;
        ArrayList<String> MovieNames = new ArrayList<>();

        try (BufferedReader br = new BufferedReader(new FileReader("Movielist.txt"))) {

            while ((MovieList = br.readLine()) != null) {
                MovieNames.add(MovieList);
            }

            for(String movieName: MovieNames){
                System.out.println(movieName);
            }

            Random r = new Random();

System.out.println(MovieNames.get(r.nextInt(MovieNames.size())));
        }

        catch(FileNotFoundException exception) {
            System.out.println("I cannot find your file");
        }
        //pick random movie
    }
}