how to multidimensional array Object to String in java

public class test {
    public static void main(String[] args) {

        Object[][] obj = { { "1", "2", "3" }, { "1", "2", "3" }, { "1", "2", "3" } };

        System.out.println(Arrays.deepToString(obj));


        String[][] argument = Arrays.stream(obj).map(a -> Arrays.stream(a).map(Object::toString).toArray(String[]::new)).toArray(String[][]::new);

        for (int i = 0; i < argument.length; i++) {
            for (int k = 0; k < argument[i].length; k++) {
                System.out.println(argument[i][k]);
            }
        }
    }
}