Java/com/study/demo5/FileStat.java

package com.study.demo5;

import java.io.*;

public class FileStat {
  public long countBytes(String filePath) {
    long totalBytes = 0;

    try (FileInputStream fis = new FileInputStream(filePath)) {

      byte[] buffer = new byte[1024];
      int bytesRead;

      while ((bytesRead = fis.read(buffer)) != -1) {
        totalBytes += bytesRead;
      }

    } catch (IOException e) {
      System.err.println("文件读取失败: " + e.getMessage());
      return -1;
    }

    return totalBytes;
  }
}