How to make an array of arrays in Java

Creating an array of arrays in Java, also known as a two-dimensional (2D) array, is useful when you want to represent data in a grid or table format—like rows and columns. Think of it as a matrix where each row is itself an array.

Here's how you can create and use one:

1. Declaration and Initialization

You can declare and initialize a 2D array in a couple of ways:

  int[][] matrix = new int[3][4];  // 3 rows and 4 columns

Or initialize it directly with values:

int[][] matrix = {

    {1, 2, 3},

    {4, 5, 6},

    {7, 8, 9}

};

2. Accessing Elements

You can access elements using two indices—one for the row and one for the column:

  int x = matrix[1][2];  // This gets the element in 2nd row, 3rd column (value: 6)

3. Looping Through a 2D Array

You can use nested loops to traverse it:

for(int i = 0; i < matrix xss=removed>

When to Use It?


• Grids in games

• Tables in data processing

• Matrix operations in math applications