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import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
/**
* 读取scores.txt文件计算平均分
* 包含完整异常处理与资源自动关闭
*/
public class ScoreAverage {
public static void main(String[] args) {
// 初始化总和与计数
int sum = 0;
int count = 0;
// try-with-resources 自动关闭流,无需手动调用 close()
try (BufferedReader br = new BufferedReader(new FileReader("scores.txt"))) {
String line;
// 逐行读取文件
while ((line = br.readLine()) != null) {
// 去除行首尾空白(避免空行/空格干扰)
line = line.trim();
// 跳过空行
if (line.isEmpty()) {
continue;
}
// 数字格式转换与累加
sum += Integer.parseInt(line);
count++;
}
// 计算并输出平均分(处理无数据情况)
if (count > 0) {
double average = (double) sum / count;
System.out.printf("总分:%d,人数:%d,平均分:%.2f%n", sum, count, average);
} else {
System.out.println("文件中无有效成绩数据");
}
} catch (java.io.FileNotFoundException e) {
// 捕获:文件不存在/无法读取
System.out.println("错误:文件未找到 - " + e.getMessage());
} catch (NumberFormatException e) {
// 捕获:行内容非有效整数
System.out.println("错误:数据格式非有效整数 - " + e.getMessage());
} catch (IOException e) {
// 捕获:读取文件时的IO异常
System.out.println("错误:读取文件失败 - " + e.getMessage());
}
}
}