java 后台如何判断上传图片大小。

Question

java 后台如何判断上传图片大小。File file = new File(path + "\" + fileName+".jpg");
long size = file.length();

        size不好用呢

Answer 1

 import java.io.File;

public class Main {
   public static long getFileSize(String filename) {
      File file = new File(filename);
      if (!file.exists() || !file.isFile()) {
         System.out.println("File doesn\'t exist");
         return -1;
      }
      return file.length();
   }
   public static void main(String[] args) {
      long size = getFileSize("c:/java.txt");
      System.out.println("Filesize in bytes: " + size);
   }
}