Java 数组仅打印最后一个存储的值，数组元素删除仅替换元素

有人知道为什么当我打印最后一条消息（“报告标题..等等”）时，列表上的计数会更新，但我只打印最后一个人的输入值

另外，我怎样才能使只有当这个人有30个或更多的信用或少于90个信用时，他们的名字和信用才会被存储在数组中，否则对输入什么都不做

最后，在“admin review”提示部分，如果我键入与输入匹配的名称，它应该删除该名称，但在我当前的代码中，它仅用我输入的名称替换该名称

  final int MAX_ON_LIST = 50;

  String[] stuName = new String[1];
  int[] numCredits = new int[1];

  int currentSize = 0;

  String question = JOptionPane.showInputDialog("Are you done entering students? (Enter 'Y' or 'N')");

  while (question.equalsIgnoreCase("n")) {

     for (int i = 0; i < stuName.length; i++) {
        do {
           try {
              stuName[i] = JOptionPane.showInputDialog("Enter student name:");        
              currentSize++;
           }
           catch (NumberFormatException e) {
              stuName[i] = "";
           }
           if (stuName[i].equals("")) {
              JOptionPane.showMessageDialog(null, "Name cannot be blank");
           }
        } while (stuName[i].equals(""));
     }


     for (int i = 0; i < numCredits.length; i++) {

        do {
           try {
              numCredits[i] = Integer.parseInt(JOptionPane.showInputDialog("Enter # of completed credits:"));
           }
           catch (NumberFormatException e) {
              numCredits[i] = -1;
           }
           if (numCredits[i] < 0) {
              JOptionPane.showMessageDialog(null, "# of credits can't be less than 0");
           }
        } while (numCredits[i] < 0);
     }

     JOptionPane.showMessageDialog(null, Arrays.toString(stuName) + "\n" + Arrays.toString(numCredits));

     question = JOptionPane.showInputDialog("Are you done entering students? (Enter 'Y' or 'N')");

  }




  String nxtQuestion = JOptionPane.showInputDialog("Are you done with the admin. review? (Enter 'Y' or 'N')");



  while (nxtQuestion.equalsIgnoreCase("n")) {

     String searchValue = JOptionPane.showInputDialog("Enter a name:");;
     int position = 0;
     boolean found = false;

     while (position < stuName.length && !found) {
        if (stuName[position].equalsIgnoreCase(searchValue)) {
           found = true;
        }
        else {
           ++position;
        }
     }
     if (found) {
        stuName[1] = stuName[currentSize - 1];
        --currentSize;

        JOptionPane.showMessageDialog(null, Arrays.toString(stuName) + "\n" + Arrays.toString(numCredits));
     }
     else {
        JOptionPane.showMessageDialog(null, "Name not on list");
        JOptionPane.showMessageDialog(null, Arrays.toString(stuName) + "\n" + Arrays.toString(numCredits));

     }

     nxtQuestion = JOptionPane.showInputDialog("Are you done with the admin. review? (Enter 'Y' or 'N')");
  }



  if (nxtQuestion.equalsIgnoreCase("y")); 
  {

     JOptionPane.showMessageDialog(null, 
           "Report Header\n\n" + "# of student's on list: " + currentSize + "\nNames: " + Arrays.toString(stuName) +
           "\nCredits: " + Arrays.toString(numCredits));
  }

final int MAX_ON_LIST=50；
String[]stuName=新字符串[1]；
int[]numCredits=新int[1]；
int currentSize=0；
String question=JOptionPane.showInputDialog（“您输入学生了吗？（输入'Y'或'N'）”；
while（问题等信号情况（“n”））{
for（int i=0；i

每个数组都有一个元素。每次添加名称时，都会将其放在数组中的相同位置

String[] stuName = new String[1];
int[] numCredits = new int[1];

此循环始终只有一个过程，i=0

for (int i = 0; i < stuName.length; i++) {

for（int i=0；i

备选方案包括：

• 创建学生的

  java.util.List

  ，每次调用List.add（），学生人数会根据需要增加
• 创建学生从名字到值的

  java.util.Map

---

for循环是预编译的，因此在启动循环之前，您需要将stune设置为某个值。

我不知道为什么在列表（ArrayList或LinkedList）中使用数组会让您感到痛苦这将更好地满足您的需要。我假设这是一项必须使用数组的任务。否则，整个代码都应该重写

如上所述，数组不会更改大小-两个数组的大小始终为1。如果输入多个学生，然后在“管理”中输入最后一个学生的姓名，这也会导致索引越界异常

最后一个学生的名字是唯一保存的名字，这就是为什么它是唯一打印的名字

---

为了只存储积分>=30的人，我如何设置数组的大小，使其仅与用户得到提示的次数相同？但是，如果不询问用户希望在收到提示之前得到提示的次数，您可以进一步解释这一点吗？因此，我应该将stuName设置为while和for循环之间的某个值？如上面的said；如果单个过程仍然存在问题，则do-while循环可能比for循环更好。如果用户只想输入5个名称，它将显示这5个名称？或者，无论用户想输入多少名称，但最大值为50个名称。确定最大值的一种方法是在最顶端的out中添加一个附加条件ErMyLoor——在而不是<>代码> 时，您可能想考虑生成<代码>。您可以通过循环循环来显示所有输入的名称。当前，您的代码搜索特定的输入名称。

if (nxtQuestion.equalsIgnoreCase("y"));
{
// Do something
}

public static void main(String[] args) {
    final int MAX_ON_LIST = 50;
    final int bottomCreditsLimit = 30;
    final int topCreditsLimit = 90;

    String[] stuName = new String[0];
    int[] numCredits = new int[0];

    String question = JOptionPane.showInputDialog("Are you done entering students? (Enter 'Y' or 'N')");

    while (question.equalsIgnoreCase("n") && stuName.length < MAX_ON_LIST) {
        String stuNameInput = "";
        do {
            stuNameInput = JOptionPane.showInputDialog("Enter student name:").trim();
            if (stuNameInput.equals("")) {
                JOptionPane.showMessageDialog(null, "Name cannot be blank");
            }
        } while (stuNameInput.equals(""));

        int numCreditsInput = -1;
        do {
            try {
                numCreditsInput = Integer.parseInt(JOptionPane.showInputDialog("Enter # of completed credits:").trim());
                if (numCreditsInput < 0) {
                    JOptionPane.showMessageDialog(null, "# of credits can't be less than 0");
                }
            } catch (NumberFormatException e) {
                JOptionPane.showMessageDialog(null, "Please input integer value");
            }
        } while (numCreditsInput < 0);

        if (numCreditsInput >= bottomCreditsLimit && numCreditsInput <= topCreditsLimit) {
            stuName = Arrays.copyOf(stuName, stuName.length + 1);
            stuName[stuName.length - 1] = stuNameInput;
            numCredits = Arrays.copyOf(numCredits, numCredits.length + 1);
            numCredits[numCredits.length - 1] = numCreditsInput;
            JOptionPane.showMessageDialog(null, Arrays.toString(stuName) + "\n" + Arrays.toString(numCredits));
        }

        question = JOptionPane.showInputDialog("Are you done entering students? (Enter 'Y' or 'N')");
    }

    String nxtQuestion = JOptionPane.showInputDialog("Are you done with the admin. review? (Enter 'Y' or 'N')");

    while (nxtQuestion.equalsIgnoreCase("n")) {
        String searchValue = JOptionPane.showInputDialog("Enter a name:").trim();
        int position = -1;

        for (int i = 0; i < stuName.length; i++) {
            if (stuName[i].equalsIgnoreCase(searchValue)) {
                position = i;
                break;
            }
        }
        if (position >= 0) {
            stuName[position] = stuName[stuName.length - 1];
            stuName = Arrays.copyOf(stuName, stuName.length - 1);
            numCredits[position] = numCredits[numCredits.length - 1];
            numCredits = Arrays.copyOf(numCredits, numCredits.length - 1);
        } else {
            JOptionPane.showMessageDialog(null, "Name not on list");
        }
        JOptionPane.showMessageDialog(null, Arrays.toString(stuName) + "\n" + Arrays.toString(numCredits));

        nxtQuestion = JOptionPane.showInputDialog("Are you done with the admin. review? (Enter 'Y' or 'N')");
    }

    JOptionPane.showMessageDialog(null, "Report Header\n\n" + "# of student's on list: " + stuName.length + "\nNames: " + Arrays.toString(stuName)
            + "\nCredits: " + Arrays.toString(numCredits));
}