Java 2D array sum (addition of all)

Question

I want to sum a 2D array to this:

I want the method to sum a 2D array. However, if x is greater than y the program gets an exception. I tried to debug it, but I do not know how to fix it smoothly. Should I create another method if x is greater than y ? Points is the array with all the values.

 int x = //Random value
 int y = //Random value
 deltSum = new int[y];

 int output = 0;
 for (int t = 0; t < x; t++) {
    for (int i = 0; i < y; i++) {
        output += points[t][i]; //Add all values in the first section of the array.
    }
    deltSum[t] = output;
    System.out.println(output);
    output = 0;
 }

Answer 1

Try to assign values of x and y as below:

int x = points.length;
int y = points[].length;
deltSum = new int[y];

Understand that if the Random values are out of the index of point[][] array, then it will surely give you runtime exceptions.

Answer 2

If you want random values then use Random Class within the range of length of the array to get different and random values of x and y and avoid ArrayIndexOutOfBound exception.

import java.util.Random; //to use Random Class...

...

Random randomGenerator = new Random(); //making instance of Random

//these statements will assign a value to x & y that is random 
//and smaller than the maximum length which is specified.
int x = randomGenerator.nextInt(points.length); //Will assign random value to x less then points.length
int y = randomGenerator.nextInt(points[0].length); ////Will assign random value to x less then points[].length