java 使用 PrintWriter 将模式打印到文件

Question

我正在编写一个JAVA程序来将钻石图案打印到文件中。该模式已正确打印在控制台上，但已正确打印到文件中。这是代码:

            static void print_row(int cnt,PrintWriter output)
            {
                 while(cnt --> 0) 
                     System.out.print("* "); 
                     output.print("* "); // or for loop, I just think --> is cute
                     output.println();
                     System.out.println();
            }

            static void diamond(int maxrow, int row,PrintWriter output)
            {
                 if (row >= maxrow)
                 {
                     print_row(row,output);
                 }
                 else
                 {
                     char[] chart = new char[maxrow-row];
                     Arrays.fill(chart,' ');
                     String t = new String(chart);

                     System.out.print(t);
                     output.print(t);
                     print_row(row,output);

                     diamond(maxrow, row+2,output);
                     char[] chard = new char[maxrow-row];
                     Arrays.fill(chard,' ');
                     String d = new String(chard);
                     output.print(d);
                     System.out.print(d);
                     print_row(row,output);
                 }
            }

输出是这样的

                * 
              * 
            * 
          * 
        * 
          * 
            * 
              * 
                * 

Answer 1

print_row 中的 while 循环仅循环 System.out.println。要在 PrintWriter 的终端上获得相同的输出，您也应该将其包含在循环中:

static void print_row(int cnt, PrintWriter output)
{
    while(cnt --> 0) {
        System.out.print("* ");
        output.print("* "); // Here!
    }
    output.println();
    System.out.println();
}