Java如何获取文件的磁盘空间，如Linux的命令“du”？

Question

I know Java can use File.length(), FileChannel.size() or RandomAccessFile.length() to get a file's length, but this equals Linux's command "ls". However, when I create a file with a specific length as follows:

    RandomAccessFile randomAccessFile = new RandomAccessFile(filePath,"rw");
    randomAccessFile.setLength(10485760);

and use "ls -l filePath", I get the file's length is 10485760, but using "du filePath" only gets 0.

So, how to use Java to get the file's real used disk space?

Answer 1

As per answer to question pertaining to Windows , How do you get the file on disk, and not just the file size in Java? , there is no way to do it by one Java command, you can run Linux du from Java, have a look here for technics How to run Linux commands in Java? .