java - 打印钻石 - 无法输入？

Question

我正在尝试编写一个输出菱形图案的程序，如下所示:

   *
  ***
 *****
  ***
   *

我首先尝试让它打印钻石的上半部分。

我可以在控制台中输入“totalLines”，但当它提示输入“character”时我无法输入任何内容。为什么会发生这种情况？

我们在大多数作业中都使用 JOptionPane，因此我在这方面遇到麻烦是有道理的，但从我从阅读本书中可以看出，这是正确的。

(如果您有时间与我讨论 for 循环，我很确定它们需要改进。我将非常感激。)

public static void main(String[] args) {

    Scanner input = new Scanner(System.in);

    int totalLines, lines, currLine = 1, spaces, maxSpaces, minSpaces, numCharacters, maxCharacters, minCharacters;

    String character;

    System.out.print("Enter the total number of lines: ");
    totalLines = input.nextInt();
    System.out.print("Enter the character to be used: ");
    character = input.nextLine();

    lines = ((totalLines + 1)/2);
    // spaces = (Math.abs((totalLines + 1)/2)) - currLine;
    maxSpaces = (totalLines + 1)/2 - 1;
    minSpaces = 0;
    // numCharacters = (totalLines - Math.abs((totalLines +1) - (2*currLine)));
    maxCharacters = totalLines;
    minCharacters = 1;
    spaces = maxSpaces;

    for (currLine = 1; currLine<=lines; currLine++) {
        for (spaces = maxSpaces; spaces<=minSpaces; spaces--){
            System.out.print(" ");
            }
        for (numCharacters = minCharacters; numCharacters>= maxCharacters; numCharacters++){
            System.out.print(character);
            System.out.print("\n");
        }
        }


    }

Answer 1

尝试使用 next() 而不是 nextLine()。