以矩阵格式打印二维数组

final int[][] matrix = {  { 1, 2, 3 },  { 4, 5, 6 },  { 7, 8, 9 }};for (int i = 0; i < matrix.length; i++) {    for (int j = 0; j < matrix[i].length; j++) {        System.out.print(matrix[i][j] + " ");    }    System.out.println();}

产生：

1 2 34 5 67 8 9