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java程序没有完全完成

我正在尝试创建一个程序,该程序接收一个输入文件,该文件包含表示空格数的整数行,或者是要打印的字符,以创建图片。行上的第一个整数始终是要打印的空格数(可能是0)。每个备用整数都是要打印的字符数。一行上的最后一个整数将始终为-1,表示该行的结尾。例如,第02442-1行表示“0个空格-2个字符-4个空格-2个字符-下一行”字符可以是任何字符,如“#”或“%”

这就是我目前所拥有的

import java.io.*;
import java.util.Scanner;

public class PicturePrinter
{
private Scanner fileScanner;
private FileWriter fwriter;
private PrintWriter outputFile;

public PicturePrinter(File file, boolean appendToOutputFile) throws IOException
{
    fileScanner = new Scanner(file);
    if (appendToOutputFile)
    {
        fwriter = new FileWriter("output.txt", true);
        outputFile = new PrintWriter(fwriter);
        printPicture(true);
        outputFile.close();
    }
    else
    {
        printPicture(false);
    }
    fileScanner.close();
}

//***************

public static void main(String[] args) throws IOException
{
    String infileName;
    Scanner keyboard =  new Scanner(System.in);
    boolean badFile;
    File file;
    System.out.println("This program prints pictures from input files.");
    System.out.println("Do you need a picture printed? (y or n): ");
    String answer = keyboard.nextLine();
    while (answer.charAt(0) == 'y' || answer.charAt(0) == 'Y')
    {
        do
        {
            System.out.print("Enter your input file's name: ");
            infileName = keyboard.nextLine();
            file = new File(infileName);
            if (!file.exists())
            {
                badFile = true;
                System.out.println("That file does not exist.");
            }
            else
            {
                badFile = false;
            }
        }
        while (badFile);
        System.out.print("Would you like to export the picture to output.txt? (y or n): ");
        answer = keyboard.nextLine();
        if (answer.charAt(0) == 'y' || answer.charAt(0) == 'Y')
        {
            PicturePrinter pp = new PicturePrinter(file, true);
        }
        else
        {
            PicturePrinter pp = new PicturePrinter(file, false);
        }
        System.out.print("Would you like another picture printed? (y or n): ");
        answer = keyboard.nextLine();
    }
}

public static void printPicture(boolean picture)
{
    Scanner key =  new Scanner(System.in);
    while (key.hasNextLine())
        {
            if (key.hasNextInt() && key.nextInt() != -1)
            {
                int space = key.nextInt();
                System.out.format("[%spaces]%n", "");
                int chars = key.nextInt();
                System.out.format("[%charss]%n", "#");
            }
            else
            {
                System.out.println();
            }
       }
  }
 }

一切都可以编译,但当我运行程序时,在得到导出图片的答案后,程序将变为空白。之后什么都不做。我认为是代码底部的printPicture方法把它搞砸了。我只是不知道该怎么做来修复它

输入文件如下所示

4 3 3 -1
2 4 1 1 2 -1
1 1 1 1 1 2 1 1 1 -1
0 3 2 1 1 3 -1
5 1 4 -1
2 3 1 3 1 -1
1 5 1 3 -1
1 3 1 1 1 1 1 1 -1
1 5 1 3 -1
2 3 1 3 1 -1

共 (2) 个答案

  1. # 1 楼答案

    printPicture方法应从文件中读取,而不是从标准输入中读取。换句话说,您在printPicture中使用了错误的扫描仪。卸下key扫描仪,改用fileScanner

  2. # 2 楼答案

    hasNextLine()hasNextInt()是期望输入的阻塞方法。假设您提供来自文件的输入,但是在方法printPicture()中将扫描器设置为Scanner key = new Scanner(System.in);,这就是该方法永远挂起的原因