This is an example of two-dimensional arrays in java. 2D arrays are just arrays of arrays.

public class TwoDArray {
    public static void main(String [] args) {
	int [][] arr1 = { {1, 2, 3}, {4, 5, 6} }; // 2-by-3 array
	int [][] arr2 = new int[3][2]; // memory for a new 3-by-2 array

	// initializing some elements of the new array
	// the rest of elements are zeros
	arr2[0][1] = 7;
	arr2[1][0] = 8;
	arr2[2][1] = 9;

	// priniting the first array
	for (int i = 0; i < arr1.length; i++) {
	    for (int j = 0; j < arr1[i].length; ++j) {
		System.out.println("a[" + i + "," + j + "] = " + arr1[i][j]);
	    }
	    System.out.println();
	}

	// printing out the second array
	for (int i = 0; i < arr2.length; i++) {
	    for (int j = 0; j < arr2[i].length; ++j) {
		System.out.println("a[" + i + "," + j + "] = " + arr2[i][j]);
	    }
	    System.out.println();
	}
    }
}

This is an example from CSci 2101 course.