Write a java program to compute multiplication table?

Write a Java program to compute the Multiplication table.

Write a Java program to compute multiplication tables. Consider the following multiplication table, which we denote it by M:

Multiplication table function: M[i][j] = i*j

where 1<= (i,j) <=n

Run the program and test your program with some testcases.

Java Program

import java.util.InputMismatchException;
import java.util.Scanner;

public class MultiplicationTable {
 public static void main(String[] args) {
 int n;
 Scanner input = null;
 try {
 input = new Scanner(System.in);
 System.out.println("Enter size of the array:");
 n = input.nextInt();

 if (n > 0) {
 int[][] a = computeTable(n);
 printTable(a);
 } else {
 System.out.println("Enter positive number.");
 System.exit(0);
 }

 } catch (InputMismatchException ime) {
 System.out.println("Not a valid input");
 } catch (Exception e) {
 e.printStackTrace();
 } finally {
 if (input != null) {
 input.close();
 }
 }
 }

 static int[][] computeTable(int n) {
 int[][] a = new int[n][n];
 for (int i = 0; i < n; i++)
 for (int j = 0; j < n; j++)
 a[i][j] = (i+1)*(j+1);
 return a;
 }

 static void printTable(int[][] a) {
 for (int i = 0; i < a.length; i++) {
 for (int j = 0; j < a.length; j++)
 printWithSpace(a[i][j],10);
 System.out.println();
 }
 }
 static void printWithSpace(int n, int z) {
 String s = "" + n, space = " ";
 int l = s.length();
 System.out.print(space.substring(0, z-l) + s);
 }
}

 

Run output

TestCase: Happy paths

Enter size of the array:
5

1      2     3     4      5
2      4     6     8    10
3      6     9    12   15
4      8   12    16    20
5    10   15    20    25

Run output 2

Enter size of the array:
10
1       2      3     4     5       6       7       8       9      10
2       4      6     8   10     12      14     16     18     20
3       6      9   12   15     18      21     24      27    30
4       8    12   16    20     24     28     32      36    40
5     10    15   20    25     30     35     40      45    50
6     12    18   24    30     36     42     48      54    60
7     14    21   28    35     42     49     56      63    70
8     16    24   32    40     48     56     64      72    80
9     18    27   36    45     54     63     72       81   90
10    20   30   40    50     60     70     80      90   100

 

Testcase : Unhappy paths

Enter size of the array:
0
Enter positive number.

Another run

Enter size of the array:
table
Not a valid input