Question

您好我有一个加载值的应用程序。值为x，y和字符串值。我想知道如何加载一个字符串，因为我只知道如何使用整数。看看这段代码：

    public static void loadStars() {
    try {
        BufferedReader bf = new BufferedReader(new FileReader   ("files/cards.txt"));
        for (int i = 0; i < 10; i++) {
            String line;
            while ((line = bf.readLine()) != null) {

                String[] args = line.split(" ");

                int x = Integer.parseInt(args[0]);
                int y = Integer.parseInt(args[1]);
                String name = Integer.parseInt(args[2]);

                play.s.add(new Star(x,y,name));


            }
        }

        bf.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

我有

play.s.add(new star(x,y,name));

我知道如何加载x和y，但我不知道如何加载name。请帮帮我。

修改----

在其中加载的文件格式如下：

x y name

示例：

10 10 jack
100 500 conor

每颗星由1行代表。

public class Star extends BasicStar {

    private Image img;

    public Star(int x, int y,String starname) {
        this.x = x;
        this.y = y;
        this.starname = starname;

        r = new Rectangle(x, y, 3, 3);
    }

    public void tick() {

        if (r.contains(Comp.mx, Comp.my) && Comp.ml) {
            remove = true;
        }
    }

    public void render(Graphics g) {
        if (!displaySolar) {

            ImageIcon i2 = new ImageIcon("res/planets/star.png");
            img = i2.getImage();
            g.drawImage(img, x, y, null);
        }
    }
}

Answer 1

Array args []已经是String，所以你只需要改变

String name = Integer.parseInt(args[2]);

到

String name = args[2];

就是这样。

Answer 2

试试这个。

public static void loadStars() {
        try {
            BufferedReader bf = new BufferedReader(new FileReader   ("files/cards.txt"));
            for (int i = 0; i < 10; i++) {
                String line;
                while ((line = bf.readLine()) != null) {

                    String[] args = line.split(" ");

                    int x = Integer.parseInt(args[0]);
                    int y = Integer.parseInt(args[1]);
                    String name = args[2]; // args array contain string, no need of conversion.

                    play.s.add(new Star(x,y,name));


                }
            }

        bf.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Answer 3

使用StringTokenizer改进代码。试试这个。

    public static void loadStars()
        throws IOException {
    String line;
    BufferedReader bf = new BufferedReader(new FileReader   ("files/cards.txt"));
    try
    {
    while((line = bf.readLine()) != null)
    {
        if (line == null || line.trim().isEmpty())
            throw new IllegalArgumentException(
                    "Line null!");

        StringTokenizer tokenizer = new StringTokenizer(line, " ");
        if (tokenizer.countTokens() < 3)
            throw new IllegalArgumentException(
                    "Token number not valid (<= 3)");
        int x, y;
        String xx = tokenizer.nextToken(" ").trim();
        String yy = tokenizer.nextToken(" ").trim();
        String name = tokenizer.nextToken(" ").trim();
        try
        {
        x = Integer.parseInt(xx);
        }catch(ParseException e){throw new IllegalArgumentException(
                "Number format not valid!");}
        try
        {
        y = Integer.parseInt(yy);
        }catch(ParseException e){throw new IllegalArgumentException(
                "Number format not valid!");}
        play.s.add(new Star(x,y,name));
    }
    } catch (NoSuchElementException | NumberFormatException | ParseException e) {
        throw new IllegalArgumentException(e);
    }
}

Answer 4

Array args []已经是String，所以你只需要改变

String name = Integer.parseInt(args[2]);

// If you are using this values anywhere else you'd do this so de GC can collects the arg[] array
String name = new String(args[2]);

请注意，如果字符串参数中有空格，则每个单词都将是一个新参数。如果你有这样的电话：

java -jar MyProgram 1 2 This is a sentence.

你的arg []将是：

{"1", "2", "This", "is", "a", "sentence."}

如果你需要句子是一个字符串，你应该使用撇号：

java -jar MyProgram 1 2 "This is a sentence."

你的arg []将是：

{"1", "2", "This is a sentence."}

java如何加载字符串值

4 个答案: