自定义异常捕获并向终端返回不正确的值

Question

使用此代码，我的 objective 将在终端中显示一组 ID 号，可以将其分配给 'grades'。创建它以便它可以处理异常并在发生异常时显示消息。在代码的最终输出中，数组中的所有五个变量都必须列出，超过“100”的变量被列为“0”。问题是，无论何时引发此异常，文本都不会输出到终端，并且它会将 'grades' 的所有其余部分也设置为“0”。我想知道是否有任何方法可以避免这种情况并获取代码以在 'for' 循环期间将消息输出到终端，以及避免将所有其他值替换为“0” 这是代码：

//ScoreException.Java
public class ScoreException extends Exception {
    public ScoreException(String s) {
        super(s);
    }
}

//TestScore.Java
import java.util.*;
public class TestScore {
    public static void main(String args[]) throws Exception {
        Scanner input = new Scanner(System.in);
        int[] ids = {1234, 2345, 3456, 4567, 5678};
        int[] scores = {0, 0, 0, 0, 0};
        String scoreString = new String();
        final int HIGHLIMIT = 100;
        String inString, outString = "";
        for (int x = 0; x < ids.length; ++x) {
            try{
                System.out.println("Enter score for student id number: " + ids[x]);
                inString = input.next();
                if(scores[x]>HIGHLIMIT){
                    throw new ScoreException("Score over 100");
                }
            }catch(ScoreException e){
                scores[x]=0;
                System.out.println("Score over 100");
            }
        }
                
        for (int x = 0; x < ids.length; ++x)
            outString = outString + "ID #" + ids[x] + "  Score " + scores[x] + "\n";
        System.out.println(outString);
    }
}

Answer 1

永远不会抛出您的异常。 scores 数组的任何元素都没有赋值，因此它们保持为 0。因此表达式 scores[x]==HIGHLIMIT 永远不会为真。也不应该是scores[x] > HIGHLIMIT吗？

Answer 2

您需要将输入分配给数组的当前索引。另外，如果出现异常，您需要减少计数器。

import java.util.Scanner;

class ScoreException extends Exception {
    ScoreException(String message) {
        super(message);
    }
}

class Main {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int[] ids = { 1234, 2345, 3456, 4567, 5678 };
        int[] scores = { 0, 0, 0, 0, 0 };
        final int HIGHLIMIT = 100;
        String outString = "";
        for (int x = 0; x < ids.length; ++x) {
            try {
                System.out.print("Enter score for student id number, " + ids[x] + ": ");
                scores[x] = input.nextInt();// Assign the input to the current index of the array
                if (scores[x] > HIGHLIMIT) {
                    throw new ScoreException("Score over 100");
                }
            } catch (ScoreException e) {
                System.out.println("Score over 100");
                --x;// Decrease the counter
            }
        }

        for (int x = 0; x < ids.length; ++x)
            outString = outString + "ID #" + ids[x] + "  Score " + scores[x] + "\n";
        System.out.println(outString);
    }
}

样本运行:

Enter score for student id number, 1234: 89
Enter score for student id number, 2345: 102
Score over 100
Enter score for student id number, 2345: 78
Enter score for student id number, 3456: 110
Score over 100
Enter score for student id number, 3456: 90
Enter score for student id number, 4567: 87
Enter score for student id number, 5678: 86
ID #1234  Score 89
ID #2345  Score 78
ID #3456  Score 90
ID #4567  Score 87
ID #5678  Score 86

自定义异常捕获并向终端返回不正确的值

Custom Exception Catching and Returning Incorrect Values to The Terminal

java

for-loop

exception

java.util.scanner