generar una matriz de 3 por 3

ublic static void main(String[] args) {
    int [][] matrix = new int[3][3];
    matrix[0][0] = 1;
    matrix[0][1] = 2;
    matrix[0][2] = 3;
    matrix[1][0] = 4;
    matrix[1][1] = 5;
    matrix[1][2] = 6;
    matrix[2][0] = 7;
    matrix[2][1] = 8;
    matrix[2][2] = 9;

    System.out.println(