Given a square matrix m3x3 create a java code to calculate t

Given a square matrix m[3x3], create a java code to calculate the value of its SECONDARY Diagonal. See example below.

Example given matrix m[3x3] shown below:

Secondary Diagonal (generic m[3x3]) = m[0,2] + m[1,1] + m[2,0]
Secondary Diagonal (as in the example above) = 11 + 8 + 2 = 21

Note 1: Your java code MUST be GENERIC to calculate the secondary diagonal of ANY square matrix [2x2], [3x3],[4x4], etc. (Use a constant in your code to set the values of numberOfRows and numberOfColumns of your matrix.

Note 2: Your matrix m may be hardcoded (no need of user interaction)

Note 3: In case numberOfRows and numberOfColumns ar differents, your program must display the following message: “This is not a square matrix.”

Solution

public class Test{
   public static void secDiag(int matrix[][]){
       for(int i = 0; i < matrix.length; i++){
           if(matrix.length != matrix[i].length){
               System.out.println(\"This is not a square matrix.\");      
               return;
           }
       }

       int sum = 0;
       for(int i = 0; i < matrix.length; i++){
           sum += matrix[i][matrix.length - i - 1];
       }
       System.out.println(\"Secondary Diagonal = \" + sum);
   }
  
   public static void main(String args[]){
       int arr[][] = {{10, 12, 11}, {9, 8, 31}, {2, 16, 24}};
       secDiag(arr);
   }
}