java/w7/ScoreAverageCalculator.java

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class ScoreAverageCalculator {
    public static void main(String[] args) {
        int sum = 0;
        int count = 0;

        // try-with-resources 自动关闭流
        try (BufferedReader br = new BufferedReader(new FileReader("scores.txt"))) {
            String line;
            while ((line = br.readLine()) != null) {
                line = line.trim();
                if (line.isEmpty()) {
                    continue;
                }
                int score = Integer.parseInt(line);
                sum += score;
                count++;
            }

            if (count > 0) {
                double average = (double) sum / count;
                System.out.printf("总分：%d，有效成绩数：%d，平均分：%.2f%n", sum, count, average);
            } else {
                System.out.println("文件无有效成绩！");
            }
        } catch (java.io.FileNotFoundException e) {
            System.out.println("错误：文件未找到或无法访问！" + e.getMessage());
        } catch (NumberFormatException e) {
            System.out.println("错误：包含非数字数据！" + e.getMessage());
        } catch (IOException e) {
            System.out.println("错误：读取文件失败！" + e.getMessage());
        }
    }
}