Laba_7_1

package com.company;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Scanner;

public class Main {

    public static Scanner scan = new Scanner(System.in);
    public final static String MISTAKE_NOT_FOUND_MESSAGE = "Error! A file with the same name was not found. Try again.";
    public final static String MISTAKE_NOT_OPEN_MESSAGE = "Error! Unable to open this file. Please check the file and try again..\n";

    public static void main(String[] args) {
        System.out.println("Данная программа преобразует матрицу инцидентности\n" + "в списки инцидентности.");
        int matrix[][] = readFile();
        System.out.println("Read file:");
        outputInConsole(matrix);
        String[] res = createList(matrix);
        outputResult(res);
        System.out.println("\nProgram completed.");
    }

    public static void outputInConsole(int arr[][]) {
        for (int i = 0; i < arr.length; i++) {
            for (int j = 0; j < arr[0].length; j++) {
                System.out.print(arr[i][j] + "   ");
            }
            System.out.println();
        }
    }

    public static String getFileName() {
        final String INPUT_MESSAGE = "Please enter a file name from which data will be read.\nFor example,\"C:\\Users\\Eugene\\Desktop\\Name.txt\".";
        System.out.println(INPUT_MESSAGE);
        String fileName = scan.nextLine();
        return fileName;
    }

    public static void outputResult(String[] res) {
        System.out.println("Result:");
            for (int i = 0; i < res.length; i++) {
                System.out.println((i+1) + ". " + res[i]);
            }
        }

    public static int[][] readFile() {
        boolean isInvalidInput;
        int[][] matrix = null;
        do {
            isInvalidInput = false;
            String fileName = getFileName();
            try {
                BufferedReader input = new BufferedReader(new FileReader(fileName));
                String text = input.readLine();
                int row = Integer.parseInt(text);
                text = input.readLine();
                int column = Integer.parseInt(text);
                matrix = new int[row][column];
                for (int i = 0; i < row; i++) {
                    text = input.readLine();
                    String[] arrFilling = text.split(" ");
                    for (int j = 0; j < column; j++) {
                        matrix[i][j] = Integer.parseInt(arrFilling[j]);
                    }
                }
                input.close();
                isInvalidInput = checkMatrix(matrix);
            } catch (FileNotFoundException e) {
                System.out.println(MISTAKE_NOT_FOUND_MESSAGE);
                isInvalidInput = true;
            } catch (IOException e) {
                System.out.println(MISTAKE_NOT_OPEN_MESSAGE);
                isInvalidInput = true;
            } catch (NullPointerException e) {
                System.out.println("Error! Please ckeck file.");
                isInvalidInput = true;
            } catch (NumberFormatException e) {
                System.out.println("Error! The file contains invalid data. Please check the file and try again.");
                isInvalidInput = true;
            }
        } while (isInvalidInput);
        return matrix;
    }

    public static boolean checkMatrix(int[][] matrix) {
        int i = 0;
        while (i < matrix.length) {
            int j = 0;
            while (j < matrix[0].length) {
                if ((matrix[i][j] != 1) & (matrix[i][j] != -1) & (matrix[i][j] != 0)) {
                    System.out.println("Error! В матрице есть элементы не равные {-1, 0, 1}.");
                    return true;
                }
                j++;
            }
        i++;
        }
        return false;
    }

    public static String[] createList(int[][] matrix) {
        String[] res = new String[matrix.length];
        int count = 0;
        for (int i = 0; i < matrix.length; i++) {
            String s = "";
            for (int j = 0; j < matrix[0].length; j++) {
                if (matrix[i][j] == 1) {
                    for (int k = 0; k < matrix.length; k++) {
                        if ((matrix[k][j] == 1 || matrix[k][j] == -1) && !(k == i)) {
                            s = s + (k + 1) + " ";
                        }
                    }
                }
            }
            res[count] = s;
            count++;
        }
        return res;
    }

}