将结果保存到文本文件

时间:2014-02-06 17:25:30

标签: java arrays format save

我正在制作一个骰子滚动项目,并希望将我的项目保存到.txt或.pdf文件中,以便我可以在excel中绘制图形。我刚刚学会了如何将程序保存为计算机科学课程中的文件,但有时我很难理解我的教授。有人能指出我所缺少的东西,并可能稍微解释一下这个概念吗?我试图谷歌某种解释,但我需要的是关于如何将其保存到文件的准系统解释。

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Random;

import javax.swing.JOptionPane;

public class Lab1 {

    private static int N = 0;
    private static int M = 0;
    private static Random rnd = new Random();   
    private final static int FACENUMBER = 6;
    static String output = "output.txt";
    static File file = new File(output);

    public Lab1(){

    }

    public static void main(String[] args) {

        N = Integer.parseInt(JOptionPane.showInputDialog("How many dice would you like to roll?"));
        System.out.println("Dice: "+N);

        M = Integer.parseInt(JOptionPane.showInputDialog("How many times would you like to roll?"));
        System.out.println("Rolls: "+M);

        System.out.println();

        int total[] = new int[(M)+1];

        for (int roll=1; roll<=M; roll++){
            total[roll] = rnd.nextInt((FACENUMBER-1)*N)+N;
        }

        System.out.printf("%3s%12s\n", "Rolls","    Sum of Rolls");

        for(int k=1; k<total.length; k++){

            System.out.printf("%3s%12s\n", k, total[k]);
        }
        try{
        BufferedWriter writer = new BufferedWriter(new FileWriter(file));
        writer.write(output);
        writer.close();

        }catch(IOException e){
            System.out.println("Can't open "+output);
            return;
        }
    }
}

1 个答案:

答案 0 :(得分:0)

当您尝试写入writer时,您尝试将输出作为变量传递:

try{
        BufferedWriter writer = new BufferedWriter(new FileWriter(file));
        writer.write(output);
        writer.close();
}

但是,输出是您的文本文件。

所以你需要创建一个String变量来获取for循环的结果:

for(int k=1; k<total.length; k++){

            System.out.printf("%3s%12s\n", k, total[k]);
        }

相反,您可以使用以下内容:

String yourString=""; //Empty string
    for(int k=1; k<total.length; k++){

               yourString=yourString + "%3s%12s\n" + k + total[k];
   }

然后而不是使用:

writer.write(output)

使用:

writer.write(yourString);