Matrix.java

import java.util.Scanner;

public class Matrix {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);

        System.out.println("Welcome to the Matrix Maker");
        System.out.println("=============================");
        System.out.println("\nHere are your options:");
        System.out.println("1 \t To enter matrix data" +
                "\n2 \t To display matrix" +
                "\n3 \t To exit\n");

        System.out.print("Enter your option here: ");
        int choiceMade = Integer.parseInt(scan.nextLine());
        int[][] yourMatrix = new int[0][0];

        switch(choiceMade) {
            case 1:
                int matrixRow = getRows(scan);
                int matrixCol = getCols(scan);
                yourMatrix = new int[matrixRow][matrixCol];
                enterMatrixData(scan, yourMatrix);
            case 2:
                printMatrix(yourMatrix);
                break;
            case 3:
                System.out.println("Goodbye!");
                System.exit(0);
            default:
                System.out.println("Invalid choice!");
        }
    }

    public static int getRows(Scanner s) {
        System.out.print("Enter the number of matrix rows: ");
        int row = Integer.parseInt(s.nextLine());

        while (row <= 0) {
            System.out.print("Enter the number Of matrix rows: ");
            row = Integer.parseInt(s.nextLine());
        }
        return row;
    }

    public static int getCols(Scanner s) {
        System.out.print("Enter the number of matrix columns: ");
        int cols = s.nextInt();

        while (cols <= 0) {
            System.out.print("Enter the number Of matrix rows: ");
            cols = Integer.parseInt(s.nextLine());
        }
        return cols;
    }

    public static void enterMatrixData(Scanner s, int[][] m) {
        for (int i = 0; i < m.length; i++) {
            for (int j = 0; j < m[i].length; j++) {
                System.out.printf("Enter value for Row %,d, Column %,d: ", i+1, j+1);
                m[i][j] = s.nextInt();
            }
        }
    }

    public static void printMatrix(int[][] matrix) {

        if (matrix.length == 0) {
            System.out.println("Matrix is empty!");
        } else {
            for (int[] rowVals : matrix) {
                for (int colVals : rowVals) {
                    System.out.print(colVals + "\t");
                }
                System.out.println();
            }
        }
    }
}