Rotate Image

You are given an n x n 2D matrix representing an image.

Rotate the image by 90 degrees (clockwise).

Follow up:
Could you do this in-place?

public class Solution {
    //Time: O(n^2)  Space: O(1)
    public void rotate(int[][] matrix) {
        if (matrix == null || matrix.length == 0) {
            return;
        }
        
        int n = matrix.length;
        for (int i = 0; i < n / 2; i++) {
            for (int j = 0; j < (n + 1) / 2; j++) {
                int temp = matrix[i][j];
                matrix[i][j] = matrix[n - j - 1][i];
                matrix[n - j - 1][i] = matrix[n - i - 1][n - j - 1];
                matrix[n - i - 1][n - j - 1] = matrix[j][n - i - 1];
                matrix[j][n - i - 1] = temp;
            }
        } 
    }
}