We just need a temporary variable to start swapping the values at corresponding indexes in the rotate array.

```
for(int i=0;i<matrix.length/2;i++) {
for(int j=i;j<matrix[i].length-1-i;j++) {
int tmp = matrix[i][j];
matrix[i][j] = matrix[matrix[i].length-j-1][i];
matrix[matrix[i].length-j-1][i] = matrix[matrix.length-1-i][matrix.length-1-j];
matrix[matrix.length-1-i][matrix.length-1-j] = matrix[j][matrix.length-1-i];
matrix[j][matrix.length-1-i] = tmp;
}
}
```