IO练习：随机生成1000个[50，1000）的整数，按照每行10的方式，输出 到文件中，并依次读出文件中每行的首个数字累计求和并输出 java代码

生成随机数的Java代码如下：

import java.io.FileWriter;
import java.io.IOException;
import java.util.Random;

public class RandomNumberGenerator {
    public static void main(String[] args) {
        Random random = new Random();
        FileWriter fileWriter = null;
        try {
            fileWriter = new FileWriter("random_numbers.txt");
            for (int i = 0; i < 1000; i++) {
                int randomNumber = random.nextInt(950) + 50; // 生成50到999之间的随机数
                fileWriter.write(randomNumber + " ");
                if ((i + 1) % 10 == 0) { // 每10个数字换一行
                    fileWriter.write("\n");
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                fileWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

读取文件中每行的首个数字并累加求和的Java代码如下：

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

public class RandomNumberSum {
    public static void main(String[] args) {
        FileReader fileReader = null;
        BufferedReader bufferedReader = null;
        int sum = 0;
        try {
            fileReader = new FileReader("random_numbers.txt");
            bufferedReader = new BufferedReader(fileReader);
            String line = null;
            while ((line = bufferedReader.readLine()) != null) {
                String[] numbers = line.split(" ");
                sum += Integer.parseInt(numbers[0]);
            }
            System.out.println("每行首个数字累计求和为：" + sum);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedReader.close();
                fileReader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}