Question

我正在尝试编写一个程序，将两个数组从两个不同文本文件中的数字合并为第三个数组。

我已经完成了将两个数组合并到第三个数组的方法但我不知道如何从第二个文件中获取数字。

这是我目前的代码：

public static void main(String[] args) {
    int[] mergedArray = {};

    Scanner input = new Scanner(System.in);

    System.out.println("Enter the name of your first file (including file extension): ");
    String filename = input.next();

    int[] firstArray;
    try (Scanner in = new Scanner(new File(filename)))
    {
        int count = in.nextInt();

        firstArray = new int[count];
        firstArray[0] = count;

        for (int i = 0; in.hasNextInt() && count != -1 && i < count; i++) {
            firstArray[i] = in.nextInt();
        }



    } catch (final FileNotFoundException e) {
        System.out.println("That file was not found. Program terminating...");
        e.printStackTrace();

    }
}

感谢任何帮助。

Answer 1

如果我理解正确，您只需创建一个新的扫描仪，每个文件一个。像那样：

public static void main(String[] args) {
    int[] mergedArray = {};
    Scanner input = new Scanner(System.in);
    System.out.println("Enter the name of your first file (including file extension): ");
    String filename1 = input.next();
    System.out.println("Enter the name of your second file (including file extension): ");
    String filename2 = input.next();
    int[] firstArray = null;
    int[] secondArray = null;
    try {
        Scanner in = new Scanner(new File(filename1));
        int count = in.nextInt();
        firstArray = new int[count];
        firstArray[0] = count;
        for (int i = 0; in.hasNextInt() && count != -1 && i < count; i++) {
            firstArray[i] = in.nextInt();
        }
    } catch (final FileNotFoundException e) {
        System.out.println("That file was not found. Program terminating...");
        e.printStackTrace();
    }
    try {
        Scanner in2 = new Scanner(new File(filename2));
        int count = in2.nextInt();
        secondArray = new int[count];
        secondArray[0] = count;
        for (int i = 0; in2.hasNextInt() && count != -1 && i < count; i++) {
            secondArray[i] = in2.nextInt();
        }
    } catch (final FileNotFoundException e) {
        System.out.println("That file was not found. Program terminating...");
        e.printStackTrace();
    }
    // do the merge operation with the 2 arrays
}

Answer 2

试试这个

import java.io.*;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.Files;
import java.nio.file.LinkOption;
import java.util.Scanner;
import static java.lang.System.*;
import java.util.Collection;
import java.util.Collections;
import java.util.ArrayList;
import java.util.Arrays;

public final class TwoSourceMergeOne{
    public static void main(String[] args) {
        Integer [] mergedArray = null;

        try(Scanner console = new Scanner(in)){
            out.println("Enter the Source file names (including file extensions) : ");
            out.print(">> ");
            String sourceX = console.next();
            out.print("\n>> ");
            String sourceY = console.next();

            Path sourceXPath = Paths.get(sourceX);
            Path sourceYPath = Paths.get(sourceY);

            if(!Files.exists(sourceXPath,LinkOption.NOFOLLOW_LINKS) || !Files.exists(sourceXPath,LinkOption.NOFOLLOW_LINKS)){
                out.println("Sorry. Some source files are missing. Please make sure that they are available !");
                return;
            }

            Scanner xInput = new Scanner(new FileInputStream(sourceXPath.toFile()));
            Scanner yInput = new Scanner(new FileInputStream(sourceYPath.toFile()));

            Collection<Integer> sourceXData = new ArrayList<>();
            Collection<Integer> sourceYData = new ArrayList<>();

            while(xInput.hasNextInt()) sourceXData.add(xInput.nextInt());

            while(yInput.hasNextInt()) sourceYData.add(yInput.nextInt());

            if(!sourceXData.isEmpty() && !sourceYData.isEmpty()){
                Integer [] soure_x_array = sourceXData.toArray(new Integer[sourceXData.size()]);
                Integer [] source_y_array = sourceYData.toArray(new Integer[sourceYData.size()]);               
                mergedArray = new Integer[soure_x_array.length+source_y_array.length];

                int index = 0;
                for(int x : soure_x_array) mergedArray[index ++] = x;
                for(int y : source_y_array) mergedArray[index ++] = y;

                out.printf("The merged array is = %s",Arrays.toString(mergedArray));
            }else{
                out.println("Sorry. No input data !!!");
            }
        }catch(IOException cause){ cause.printStackTrace();}
    }
}

两个源文件应与程序位于同一文件夹中。

从两个源文件获取文件输入

2 个答案: