java - 如何发现此错误代码中的错误的过程？

Question

我有这个代码:

当我启动它时，我能够得到数字 i = 0 到 i = 10。但是我知道这不是代码的目标，因为目标是进入扫描器。但是扫描仪似乎不起作用？我是在导入文件时出错还是与代码有关？我是菜鸟。

package buggyProgram;

import java.util.Scanner;

public class BuggyProgram {

  /**
   * The main method of the program. This is where it all starts.
   */
  public static void main(String[] args) {
  String[] saNames = new String[5];
  String[] saNumbers = new String[5];

  Scanner scIn = new Scanner(System.in);
    for (int i = 0; i <= 4; i++) {
        System.out.print("Enter name: ");
        saNames[i] = scIn.nextLine();

        System.out.print("Enter number: ");
        saNumbers[i] = scIn.nextLine();
    }

    System.out.println();

    for (int i = 1; i < 4; i++) {
        System.out.println("The number of " + saNames[i] + " is "
                + saNames[i] + ".");
    }
  }
}

Answer 1

Java 数组从 0(而不是 1)开始，并且您将同一个数组元素打印两次(在您的第二个 for 循环中)。最后，您始终可以使用调试器来帮助您确定哪些地方不再像您预期的那样工作。

// for (int i = 1; i < 4; i++) {
for (int i = 0; i <= 4; i++) { // <-- to match your first loop.
    System.out.println("The number of " + saNames[i] + " is "
            + saNumbers[i] + ".");
}

您也可以使用格式化输出(formatter syntax)

for (int i = 0; i <= 4; i++) {
    System.out.printf("The number of %s is %s.%n", saNames[i], saNumbers[i]);
}